Ok, here's an odd question... What exactly is a "DAY" in terms of Extended Test intervals? For example, Programming something that requires you to make a check once per day... Obviously that can't be 24 hours since the normal person needs 8 hours of sleep... Does that also account for breaks and just taking some time to stretch your legs?

Now factoring that all in, throw in a Sleep Regulator Bioware ontop of that.... How many tests should a player get within that 1 day interval?

I would say for simplicity 3 with sleep reqlaters 2 with the sustenance power. If the player with the regulaer doesn't sleep doesn't sleep.
On a side note how would having both effect you 1hours sleep(or less) a day?

Personally I don't think that anyone can remain 100% productive for an entire day. Even if you scarcely sleep you still require some down time. The same problem arises with drugs like Long Haul, which negate the need for sleep for a while.

I would permit 2 tests a day if a worker is not sleeping much or at all. I might consider allowing a third test if something is time critical, and it makes for a good story.

In SR3 a "day" of work was 4+willpower hours. You could extend the duration with a willpower test. Even if you don't have to sleep, it's hard to spend all your time working on the same thing.

Depends on how into it you are. When working on a new character concept, or some other project that really interests me, I can stay at it for days pretty much non-stop. I won't sleep, and rather than stopping to eat I'll drag my books into the kitchen and grab a quick bite with one eye still on the page and most of my concentration on the project.

Then again, I'm just badass/lame like that...

I'm with you there Rad. Not really with char concepts, I'm pretty lazy there but when it comes down to researching things I care about.
Some people can be highly productive for a sustained period and properly focussed on the tasks.

But it is really hard to grasp within a gamesystem, so I'd just handwave it.
You could go with the SR3 4+wil or just assume 8 hours as a 'normal' workload each day, but you'd throw the high-productive people out of the window with that and overestimate some others.
I am still trying to figure out why some people can do it and some just can't. Please let me know in case you find an answer.

i'll hazard a guess and say:"because not everyone can do what he really WANTS and LIKES to do"
i can spend days playing with cats/kittens and do close to nothing else aside from eating and sleeping a little bit . .
i can tell the world to go fuck itself and hole up with a book and some munchies too . .
i could not, for the life of me, keep concentrating on doing research even on things that i like for an extended period of time, because doing research gets boring as hell to me in no time and i'd rather enjoy what interests me instead of finding out the how/why about whatever it is . .

Also, different people have different focus based on brain chemistry. Extreme examples are manic/depressive and ADHD, but there's variation in the normal spectrum as well.

They are related. The chems that cause a loss of focus are teh ones released when depressed or bored. I suppose the real question is what purpose boredom serves? Why did we evolve a sense of boredom?

probably so we try something else when we're depressed with one thing, because often times when you're depressed you will become bored by the same chemical cocktail cursing through your veins . . so you try something else, maybe it makes you angry, maybe it makes you sad, maybe it doesn'T do anything for you, but maybe it makes you happy again O.o