Here is some information I have collected from the minds of Dumpshockers over the years. (The matrix run through was a good source for information if you are looking for a specific thread to search.)
DeckersThe most important attribute when decking is
Detection FactorUse Masking Mode whenever possible (if your GM is using the Matrix sb that is), your Detection Factor is your most important attribute while decking and this is the easiest way of raising it with the Rating 6 caps on beginning programs.
If using Program Options from the Matrix sb use Sneak and Stealth options on relevant Utilities. They add significantly to Program size but are worth it.
Modes are in
Matrix.123
Take the HIGHEST Sleaze utility you can afford.
Absolute essentials are:
Sleaze (to increase Detection Factor)
Deception (to log on)
Browse (to find stuff)
Read / Write (to access data files of any sort)
Spoof (to muck around with slaved devices)
Extremely useful utilities are:
Decrypt (as often files, slaves and even subsystems are encoded)
Analyze (to determine what something is).
Cloak (aids Combat maneuvers, ideal for helping you evade)
Relocate (to overcome Trace IC)
8 Things to do as a Decker:
* Upgrade everything.
* Check the Program Options for anything that gives you an edge.
* Once you're experienced enough that it won't bog you down, use Frames.
* Prepare several alternative Program load outs. Different runs have different demands.
* Do a recon hack if you have time to let the Tally settle back down, see where everything is and that'll save you time and Tally during the main event.
* During recon make sure to create a legitimate account. Helps significantly in cybercombat and if you log on through the new account your prior Tally should be gone.
* Plan out the Matrix run after the recon. Make sure you're not distracted by incidentals.
* If you get in over your head, jack out, don't tarry.
Frames and agents give a decker the same versatility that a drone rigger has, basically. if you're going to use a frame or agent, they should basically be single-purpose: combat, auto-validation, scouting, searches, whatever. pick a single task type, and build the frame or agent to accomplish that task type and only that task type. unlike drones, though, you can upload multiple copies of a single frame or agent. insanely handy.
Want to be primarily a decker who can supply drone support (and can use drones to aid in combat or as info feeds)? Rigger Protocol Emulation Modules are your friend. No jumping in, but you've got plenty of captain's-chair goodness.
'just a decker'
datajack, encephalon rating 2, and a Math SPU rating 3.
Then calculated how much Active Mem it would take to have all the basic programs at level 6. Ie: all programs EXCEPT the following: Track, Medic, and any Offensive Utilities.
Came to 1080 Active Mem needed. This is the minimum I'd want active, especially if I ever get other utilities. That means I'd have to get the Transys Highlander. CMT-Avatar is a possibility if I don't have enough cash because then I at least still have 6's in all my persona attributes and can keep all but 1 of my 'basic' programs running at level 6. Cost for all utilities, except the excluded ones listed above) and Transys = 816,000.
That gives me enough for some communication gear so I go for Transducer, Rating 6 CommLink, Radio (Rating 1 since I have the commlink), and Telephone (all Basic Grade) for a total cost of 39,700 which when added to Basic Grade Encephalon, Math SPU, and datajack, comes to 166,700. Add in a cybereye (for future enhancements) and an image link for the phone and other stuff for 6,600 and 0.2 essence. Add in the board and I get 989,300 and 3.75 Essence spent. Enough for 2 months Middle Lifestyle.
Int of 6(

against a 9 MPCP so I take Exceptional and Bonus attribute merits for Intelligence for a 7(9) giving me a 6 + 3 + 2 for 11 hacking pool. Quickness and Body at 5, all other attributes at 4 (dwarven character). Computers, Computers B/R, Electronics, Electronics B/R all at 6, Computer specialized in Decking for 5/7. Instruction at 3 (part time teacher, bonus flaw I can use for other merit if I want a Codeslinger or Cracker merit I like, or maybe Hardening merit), 13 skill points left to play with.
Not using the Matrix to build the character, but still a good Decker capable of running a Red-8/12/12/10/10 system relatively easily.
Micro vision for B/R tests. Add Biotech to give the character a second function
Another approachNever start with a deck. Encephalon with the Math SPU for a total of a +5 to your hacking Pool. Level 2 Cerebral Booster is a good +1 to that Hacking Pool as well, mix with a Mnemonic Enhancer to get the skills you need later. In addition, the best deckers are also riggers, so might go for a alpha grade VCR 2, Alpha Datajack, Rigger Protocol EM 6 for taking over rigged buildings, and a Rigg Decryption Module 6 to assist. Course by now you're up to having only 1.76 of available essence or 3.16 of Bio space, and only 141,000 Nuyen left of a million. Doesn't leave a lot of space for Street Sam stuff, but you could make a good decker/rigger. Get a smartlink and some drones and you could be set. Don't forget you have a decent Task Pool with this character, so you'd also be good (if you took the skills high enough) at Electronics and other technical stuff, you could break into anything/anywhere basically.
Another No Deck approach To make a really good Combat Decker you must be willing to start WITHOUT a deck. Starting character Decks aren't squat. Without at least a Rating 8 deck you're toast against any decent host.
Instead, take resources first and get a Datajack, Math SPU-3 and anything else you think will assist your Decking (personal preferences is a CyberLeg to later put the Deck in, with an implanted Signal Booster).
Then spend left over cash to get every non-attack program at Rating 6. They're programs, not hardware of a CyberDeck, so you can start with programs and no Deck.
This means you can spend the extra resources on Combat part of a Combat Decker. Recommendations are Wired Reflexes-2 with Reflex trigger and SmartLink 2. In addition you should get CyberEyes with at least one of LowLight or Thermo (I recommend LowLight), and Image Link (it makes a SmartLink cheaper Essence-wise). Also, I'd recommend a couple more datajack. Keep one purely for a router/microtransceiver so you an communicate quietly, and one for an external GPS=Orientation system. If you install those in a Cyberlimb, you can just link them to the extra 3 router connections of your basic Datajack.
if your GM uses Rigger Security, fill that arm with Protocol Emulation, Decryption, Etc and make sure your Willpower is starting out at 6+.
Recommended Stats are 6+ in Int and Will. 4+ in Body and Quickness. Strength and Charisma are not really needed.
Recommended Skills are Etiquette at a level equal to your Charisma, Stealth, Athletics, Computers, Electronics, Electronics B/R and Pistols (or whatever choice of Firearm interests your char).
In a priority system, Resources are first followed by attributes and skills. Dwarf makes the best Decker.
You should also look into getting the following equipment:
-A Dataline Tap
-Off-line Storage
-Computer Kit
-Data Lock
-Vidscreen Display
-Battery Pack
-Casing
-Credstick Reader
-Printer
It's always useful to have the charts on page 162 thru 164 of the "Matrix" sb with you as a crib sheet when running decking. It facilitates System Operations immensely and works as a quick reference for all Matrix Tests. the charts at the back of Matrix are invaluable. The IC effects chart on page 166 is the perfect fast reference for the GM.
Hope this helps everyone as these are an accumulation of many others suggestions.