Hell, I went to Costa Rica for a week on my change jug once! Never underestimate the power of the Penney, espechially when saved for three or four years.I built my whole bunny habitat with spare wood I had (like old stall boards, left over plywood from other projects, old broken fence posts, etc.). I even had a roll of chain link fence I got in a barter arrangement once (one of our horse boarders was short on board for the month), so used that. All I had to buy was some more screws, hinges, gate latches, etc. Everything else was recycled.
Better yet, I still have enough materials for two more projects I want to do.... dog house (I even have a few pieces of old metal roofing) and garden fence and gate (which I'll build from scrap wood and chain link). (again, will just need to buy some fixtures).
Definitely a must have. We basically convert our jars to a WalMart gift card around Christmas time, and use it for Christmas shopping. Typically, it is about $100-$150, so a nice little additional money around the holiday.