Razor blades! ARGH! I picked up a 21 pack of Mach 3 blades at Costco and they were a good price, but my man and I swear they aren't as sharp or dull faster than the smaller packs from regular stores.
Weird.
As for printer ink, we bought a little black n white laser two years ago and have only had to change the toner once. You couldn't pay me enough to go back to ink.