I bet this cheap tool is the best bargain on this site. For 2 dollars you get a flexible 24" plastic probe that will remove an alarming amount of hair and gunk clogging your sink or shower drain. It descends easy. You can snake it down without taking off the usual drain plug. The many little reverse (and very sharp!) spines hook hair balls and other unmentionable crap as you carefully back it out. It removes grunge that liquidators won't budge. Sold as disposable, a cautious wipe will keep it going forever. We have a very hairy household; I can't keep the plumbing going without it.

-- KK

Zip-It Drain Cleaner
$2
I got mine for 99 cents at our local Ace Hardware