1Fast400 Caffeine Anhydrous, 100-Grams

Yes this stuff tastes bad, but putting it in capsules works great.
Just make sure you start small, remember a regular can of coke only has about 40mg of caffeine, so if you take a huge scoop of this your body is going to have a shock reaction to all this entering your system, which it appears happened to the previous poster. I only took 1/8 teaspoon (100mg caffeine) this morning and it woke me up instantly, I actually cleaned my room, normally I would be in a groggy slow state. But I think even 100mg caffeine was too much for me, since I'm starting to shake a little bit.
what they didn't tell you is that its really 315grams of powder but you get 200mg caffeine per 630mg powder, so it is 100grams caffeine total.

This stuff will clump so make sure you shake and stir it.

It tastes terrible even after mixing with your favorite drink. And it made me sick, I felt nauseated afterwards and vomited.