Here at Boing Boing Gadgets, we leave the foaming rants about the uselessness of MIDs to Beschizza, who can't post about one without hunting down a gazelle, ripping out its throat with his teeth and smearing its blood all over his pasty British torso while screaming and staring directly into the sun. Suffice to say, Joel and I feel similarly about them, without all the festering primal rage: Beschizza can be our avatar in this.
With that said, Canonical has quietly released their own MID-specific version of Hardy Heron for mobile internet devices. The big features include a Gecko-based browser with screen zooming for tiny displays and the usual, lovely Linux OS, optimized for all current and last generation Intel MID chipsets. If you've got a McCaslin or Menlow-based MID, you can download it now. It looks great, though doubtless that's simply because they seem to have jettisoned the merconium-brown default color scheme for this release.
Ubuntu MID Edition [Ubuntu]