I tried modafinil a couple of weeks ago. A friend of mine gets it prescribed for shift work.
He gave me a few pills to try, because I'd been up most of the weekend (not on drugs or anything - just a bit of booze and a lot of insomnia). Had 4 hours sleep sat night and none sun night. The next morning I had to go to work and train a new staff member. At that point I was so tired I couldn't focus to the point of going cross eyed.
Had 200mg modafinil and, within 15 minutes, I was awake. Ran around, got ready for work, even tidied up after the weekend a bit. My appetite was instantly gone, however. It was a little like dexis in the way that I was feeling awake and productive. And unlike dexis in the way that I wasn't jittery or euphoric.
Had a couple of coffees as well - that seemed to go down ok. On the way to work (a couple of hours after initial dose) I started to get the focus thing happening again. So I had another 100mg. That seemed to be just the ticket. I didn't get any nasty headaches, as a lot of people reported with doses over 200mg. I was able to get through the day quite well and train the new girl, even though I was exhausted. I was feeling very productive most of the day, but towards the end this feeling started to slip away and I felt a little bit like I was coming down. But a very clean comedown. I had half a bar of xanax, that smoothed things out somewhat, but I wasn't feeling very sharp anymore. It was all good though, as my job was done and everyone in the office had stopped functioning anyway.
In conclusion, I really like modafinil, might try to get a script. I don't have narcolepsy or work shifts but I do suffer from insomnia, which makes me completely useless the next day.