Is there any free monitor calibration software?

[FoxAlpha]

I use a Toshiba laptop with an external 19" ViewSonic for an extended display, naturally the two screens have a large difference in colour/ brightness and all that, I'd love to be able to calibrate them both correctly, or at least the Viewsonic.
But I'm disinclined to spend any money, (Saving for a telephoto lens )
So I was wondering if anyone knows of any effective free ones?[/code]

[Citruspers]

I'm pretty sure windows 7 has a built-in calibration software tool. I suggest you search around for that (It's not in the menu's).

[FoxAlpha]

Ahh thanks mate!
Worked like a charm, didn't even think about built in stuff

[Razvan]

This is the best free software I have. (well,it's a website)
http://www.lagom.nl/lcd-test/

I'm pretty sure it's better than any "built-in" software. A friend of mine used Nvidia calibration & it was rubish. Basically,once the colors are set & the brightness & gamma ratio as well,that's as good as you're gonna get.