Here is a looper, but low fi
http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=147&Itemid=26
And here is a delay with lots of whistles and bells.
http://buildyourownclone.com/pingpong.html
I have built the delay, and it is a lot of fun. I am into the analog decay of noise thing, and even if it is a digital delay, it does degrade nicely. The kit is not to hard, but patience is really helpful. Oh yeah here is a youtube of the thing in action
http://www.youtube.com/watch?v=oOzocTjGQYE&e
Of course they are now producing a analog delay, well in a couple of weeks, and I can't wait to get one. Will probably wait til next year, but it looks like a lot of fun.
Patrick