AOL discs, cherry pies, ketchup packets, construction-paper hearts on Valentine's Day. Just stick them up on your hay bale, and hang a big rubber flap on the backside. Or make a cardboard bale, if you have enough cardboard and steel baling/shipping straps. But I'd still use the rubber flap, unless there's someone behind the bale you don't like.

i just used really densly packed straw packed potatoe sack against a tree trunk with some spray paint for targets myself. Sometimes i'd tape pinecones to it. I hadn't thought of the catsup idea, that sounds interesting.

Cardboard boxes, stuffed with plastic bags/cardboard (go to your local licqour store for the boxes, they just tend to throw them in the trash bin anyway); this is one of the favourites at many SCA archery events. I have also used the old standby in the past - the burlap sack stuffed with rags/plastic/paper/etc., anything that will stop an arrow.

I decided to "splurge" last year and spent $40 on a straw butt that fits nicely in the back seat or the trunk of my car - as long as there is nothing bulky, such as camping gear, taking up the same space. A couple of sticks on each side of the butt (you might have to dig a few small holes to put the sticks in) to hold it up, and presto - instant target. The butt itself takes up about the same amount of space as a large "Velvet Elvis" painting or the average folding card table (36" square by 3" deep).

--Artúr Dúbh Maca'Gobhaínn - Archer/Fletcher in the Barony of Nordskogen, Kingdom of Northshield, SCA