Last month I had a chance to tour a friend's garden, and saw his very nice composting setup. He'd acquired 2-3 very nice compost tumblers over the years from neighbors.
Alas, I don't have any neighbors offering such stuff up for free. Even on eBay the least expensive compost tumbler I could find was well over $100.
A search of the internet provided inspiration. The post How to Start a Compost Bin in the City (with Little Money) sold me. My 20 gallon Rubbermaid bin cost $12, but I was able to throw in an extra lid (to catch the compost tea) for free. Five minutes with the drill, and it's done. The week's paper shreddings and vegetable bits are now happily ensconced there together.
In other news, we will be building a rain barrel later this month. Then we'll be able to combine water conservation with having 55 gallons on non-potable water in case of an emergency.