I've been using this bookmarklet I whipped up for the US Yahoo PC to SMS service found here. It lets me send 120 characters of any text I've selected on a web page to a phone. Perfect for little bits of info or URLs that I want to have handy. Yes, I know there are other toolbar things or services that'll send longer messages broken up, but I wanted to do the same with Yahoo! and a basic bookmarklet (I'm not a big fan of toolbars).
I've only tested it in FireFox - it works pretty well. Just drag/drop this link to your toolbar.
Here they are: