Donny: I've tried spelling Pi, using the bullets as an abacus (31415, 3.141,3.142) in several orientations, spelled the symbol for pi, drew a pie, a slice of pi....
Also stuck on 18. Tried all the pi references I could come up with.... Some hints for those of you stuck:
15: really, try every key on your keyboard. Figure out which ones you can press. EVERY key.
17: Google the date. Think bitmaps, and keyboard.
Juze: Hint: what's the chemical formula for water? How would you write it as a mindbender?
If you get to 15, I'm trapped there. I've figured out that the only letters on the keyboard that don't kill you are "scapx", and punctuation.