Most of the Canon "Powershot" line of cameras have a custom timer setting.
You can take up to 10 pictures spaced anywhere from 1-10, 15, 20 or 30 seconds apart.
Here's all of the Canon cameras -
http://www.dpreview.com/reviews/specs/Canon/
When you click on each camera and go down the list of specs, look for the following.
"
Self-timer - 2 or 10 sec or
custom"
(That spec is near the bottom, about 20 lines up from the last one.)
If you don't see "custom" in the Self Timer field then obviously that camera won't do what you want.