I've been on Provigil since 2005.
I started out at 100 mg. q day. It was increased to 200 mg. q day and then 200-400 mg. PRN

I gauge my dose on what I have to get through. I do 12 hour shifts, work as much OT as I possibly can when it's available, and want to function outside of my job as well as I can, and enjoy myself while doing it. I don't have any problem sleeping. I find it "clears" me so I can do what I need to do when I need to do it without wilting in the middle of doing stuff.

I don't take it every day since I don't want to wear out the effect. Generally it's 100-200 mg q day, but there are those days when I need more.

Start out small but ask for the 200 mg. pill on the scrip right from the start. You can split the pill. It's hugely expensive, but if insurance covers it, you are better off with the larger pill in case you have to increase up.

I stockpile. This is one drug I cannot live without if my insurance ever dies, and the U&C on my last refill of 200 mg pills was $2435.67 for 180 pills.

It's coming off patent soon and Cephalon has introduced a new one called Nuvigil. The only difference is one inactive isomer. (check Everyday Health for the explanation for that, it's where I got it from) so Provigil should be coming down in price soon, since the generic market will be opening up on it.