This was a new idea I got yesterday when I was shopping at Halted. Since the Sunnyvale Halted is kinda far from my house, and the Sacramento one is hellza far from my Davis apartment, I usually tend to go with parts lists for several projects I have queued up at once. Unfortunately, this means the first thing I get to do when I get home is sort out three projects worth of parts from one bag, based on the what seems to be sometimes optional markings on parts.
New trick: Bring a roll of masking tape, and then lay each project down on one strip of tape, then once they're all collected, put a second piece down on top of it. Once you get home, it's just a matter of peeling the tape apart when you have time to work on that specific project.