Hooks

[eluser]tomdelonge[/eluser]
I've never used hooks. I was wondering though. If I have a user gallery and when a user uploads a photo, I want to do several things to the photo. I want to put it on amazon s3 after several sizes of it have been made. Could I use the post_system hook to let the user go about their business after an image upload and have the system keep working on playing with the image? Is that a good idea or not.

Your thoughts...