i'm window shopping right now for Photoshop/Illustrator plugins. I'm drooling, some of this shit looks excellent. I use NO plugins now.
http://www.autofx.com/ <-------- a few of these look great, the gel one, the crease one, and the focus one especially
yes i know you can do anything a filter/plugin can do using the existing Photoshop tools but preset plugin effects can make you way more productive.
So post your favorite plugins for Photoshop or Illustrator. Flash too but since I can barely use Flash ain't gonna be on my shopping list.