Those rhinehart(sp?) cube things that look like a big dice are about the most popular I see other guys with (you can pick em up and throw them on the seat of your car for example). But if you want a more permanent one, I’m sure if you did a search for “home made targets” or “target build along” you’d find some great ideas.
I remembered Steve put up some pics of his target.. try this thread:
Here’s a photo of my old target.. same idea as Steve’s except I went to the local carpet store and they had rolls of old carpet out the back to go to the rubbish tip, they were happy for me to take them for free. I cut the carpet up into tiles which stack on top of each other. The whole thing was made from scraps so was just about free. Lasted a couple of years of regular shooting (but it’s no good for broadheads).