Red: Hirasawa Yui
Blue: Akiyama Mio
Yellow: Tainaka Ritsu
Pink: Kotobuki Tsumugi ("Mugi")
Green: Nakano Azusa
You can possibly play a guitar with these picks but their actual use is as a "Touch Pen" stylus for your Game Boys or X-Boxes or whatever the latest gadget is. I tried it on my iPhone and I can't get it to work. Good luck with yours...
Oh, and in case you're interested, you can get a big can of Mitsuya Cider with a picture of one of the cuties from Madoka Magica.
And it's only a buck. Enjoy!