Pillow drums are slightly better than nothing, and nearly free. (for me at least) You won't bother anybody, that's for sure. The "snare" is a taped up phone book. The kick pedal strikes a bit of cereal box and tissue pinned to the couch. Get the pillows propped up where they go and flump away to your heart's content. I think it's funny to pick up a pillow and say "I just added this new tom. Sweet, eh?" I'm sure there are better ways to practice, but this is where it's at for now.
UPDATE - Gave away the sofa to make room for real drums! Priorities straight. Taking lessons from a real person, and youtube "drum covers" are a good learning tool!