i think im going to make a web site on the homemade pipes ive used. heres a few:
zippo style lighther (didnt work so well)
bananna
plantain
orange
lime
lemon
apple
pear
watermelon
potato
various sized pop bottles
milk jugs
honey bears
syrup bottles
water cooler bottles
crazy staw glasses
hollow broom stick
film canister
CO2 cartridge
slurpy cups
light bulbs
weed plant stocks
dollar bills
altoid tins
paper towl rolls
toilet bowls
muffler/exaust pipe
same on the fish tank here
4 foot surgical tubing with christmas lights inserted at regular intervals to make the smoke glow

the list goes on and on...i think ill right a book