I usually don't use a pick, but for tracking accuracy with synth, I fabricate my own from--credit cards.. Nice and stiff, any size I want, plus a groovy psychodelic hologram..
Also, I would never ever advocate appropriating anything from our favorite guitar shop, but I have noticed that I sometimes forget to give back demo picks.. Oops!
I've used paperclips, and coins smashed with a hammer(for the right thickness) and other office/household utensils.. Maybe I stand in the garage and say, "How about if I try this?" too much.. But nothing works like my finger..

"Why wallow with eagles, when I can soar with pigs."
Hunter S. Thompson