Free and easy to use software for batch image watermarking/text stamping?

[Elgin Clock]

I'm looking for a free and simple to use program to make a simple watermark, or text stamp on digital image files.
Nothing fancy, just a website url on the bottom or top, or side of a bunch of pics.

Thanks in advance.

[Andrew Rudolph]

I used to use a program called media resizer from http://www.mediaresizer.com/ they have a free demo i dont know if you can do custom watermarks using it but i know the full version can.

[Brandon Martus]

If you have access to the server & know some scripting, you can do that with ImageMagick (open source, etc)

For Windows, a guy I work with uses Express Thumbnail Creator and he likes it. It's $40, but I think theres a trial version that lasts X days before losing functionality.