Anyone have a suggestion as to the process, difficulty, and length of time to invent a wholely new type of focus. I know they have rules for creating your own formula, but those are for already existing types (power, spell, weapon). I'm talking about one that provides bonus dice to a test that other foci don't provide dice for.

You'll probably have to extrapolate from the enchanting rules in Street Magic. I don't think there have ever really been rules for new focus type creation since the PCs aren't expected to be highly trained magical theorists. I'd probably take the enchanting rules, figure out the threshold they'd need for the enchanting test on a similar focus, double it and in crease the interval by 1 (see the extended test difficulties on p. 58). If the enchanting interval is already a month, then make it 2 or 3 months per interval. Either way, developing an entirely new focus should be months if not years worth of research, IMO.

Unique enchantment.

Seriously, you need to define exactly what you want the new focus to do, what tests it will add dice to, and make it comparable with existing foci. In some cases, the designer or enchanter might need to possess a specific skill, metamagic, or other quality-for example, a "mana battery" that stores "mana charges" would likely require the Absorption metamagic to design or enchant.

The only Non-Standard focus I can remember from Canon is Martin DeVries Essence Focus. I suspect that probably required Blood Magic to construct.

While you probably know more and have more experiance then me, I have a few questions.

1) How does this new focus affect game balance?

2) Should magic be used in this way? (Based upon the idea that: Magic should stay within its own realms of influence)

3) Is this something that is exclusive to the players or will the NPC's start using this new focus also?

Question 3 is really the one that lets the GM even things up. If the new focus is a powerful new magic it won't be a queit secret for very long. The Corps are always on the lookout for the Next Big Thing, and (as runners should be very well aware) will do almost anything to secure that Next Big Thing when it's discovered. The other thing to keep in mind is that not very much magically is truly new, there were 3 Ages of Magic prior to the 6th world (the 1st, 2nd, and 4th worlds) and a few beings from those ages are still wandering around. Given those two factors the GM has a fair amount of flexibility to make sure that the characters new focus does not become a unique advantage for the long term, without having to resort to just shutting the player down.

from a discussion i had recently:

Conduit Focus (spellcasting varient): +1 Spell Damage Value, +1 Drain Value

Interesting idea. Maybe change it so it adds the focus' Force to both the spells Force & Drain, as to be useful for non-damaging spells. Link it to spell types the same way spellcasting & counterspelling foci work.

As for designing formula for a new foci, I would say intervals of at least 1 month & a high threshold - probably 30+. Enforce the rule that you can only make a number of rolls equal to your dice pool.