I picked up some thick foam door knob signs at the craft store in different colors on a whim (thought I might make poppers or hoppers out of them). When I was tying a bunch of Clouser minnows I thought it sure would be handy to prep a bunch of bucktail and flash bundles ahead of time. I ended up cutting some slits along both long edges of the foam and clamping it to my desk. Now I cut off bundles of hair and/or flash and slide it into the slots. You can prep about a dozen flies worth of materials on one "card". When you are ready to tie, you just pluck the bundle out and tie it in. For me, it really makes tying a batch of flies much quicker and it's easy to make sure your hair bundles are consistent from fly to fly, both in length and in density.