I powder it by chopping/grinding with a stanley blade on a mirror, if you do it right not much flies across the room. You wanna watch out with sublingual dosing with ethlyphenidate because it's very harsh and I think some people on here got little burns under their tongues from doing this.
EDIT: Augh, I did something really foolish involving my sinuses and water yesterday, pressurised the buggers when they were slightly damp after a post-shitalin rinse, forcing water into my inner ear on one side in the process. Woke up in the night in total agony from the pressure inside my ear which gradually dissipated with lots of swallowing / yawning and let me sleep. So now I'm sitting with my head at a daft angle hoping it'll drain via the eustachian tubes... it's still kind of painful and I can't hear, but I was on the verge of going to a&e in the night, pain was insane. Don't ever force water into your sinuses.