If you just have a bunch of hard drives, here is a "5 in 3" for IDE drives. It takes up 3 5.25 bays but fits 5 IDE hard drives. There's also "3 in 2"s if you need. I have a buddy with 2 of the 5-in-3's in his full tower. He got the tower used off ebay, around 85+20 USD for shipping.
Link for 5-in-3: (search for it on pricewatch for price)
http://www.cremax.com/mb810-ide.htm