This is a good idea! I used a cheapo rack with the bottom removed to add shelves to a couple of junky dressers I bought for $25 bucks from a neighbor who's dad owned a motel that was being torn down. He had a whole garage full of it. I did it again to make more shelves later. The first one just was "retired" to Goodwilll at about age 20, and the other is sitting about 3 feet from me, with all my ham radio stuff in it.
Can't beat junk furniture for value if it works.
Big Lots and some other places on line have some really great deals on racks and shelves and stuff sometimes for insanely great prices. I got 3 pretty nice CD/DVD racks, shipped and everything, for less than $80 bucks. Gave one to my sister, with a few DVD's for Xmas, kept the other two. The cheapest I ever saw them in a store was $59.95 EACH.
My audio rack is from Big Lots, was over $50 cheaper than anywhere on line or local. Only problem with it was a stripped "speed nut", and a missing rubber cushion. Sure it's Chinese Junk, but it does the job, and looks pretty expensive.