This is super cool - it's a plugin for PocketIE that posts a bookmark to your del.icio.us account. I use and love del.icio.us quite a bit, so being able to easily post to it not only from my desktop (I like the Mac-only Pukka for that) but also from my Mobile is pretty cool. The linked page goes into a bit of detail about how much work it turned out to be to make the plugin, so let me just say how much appreciate it.
If you're a social bookmarking fiend, this thing looks like a must-have.
Update: Dale notes in the comments (click, you know, "Comments" to see it) that the plug in has now been repackaged as a easy-to-install .cab file. Cheers, Dale!