Maemo might be evolving into MeeGo, but it's going by a circuitous route that takes in some Archos 5 play along the way, albeit unofficially. A group of Archos tinkerers have been persuading Maemo (in its Mer form) to run on both the Archos 5 Internet Tablet (usually found running Android) and the Archos 5 Internet Media Tablet, and while it's not a perfect implementation it does at least function.
Video demos after the cut
Performance is actually pretty impressive, certainly on the Internet Tablet, which loads into Maemo quickly and then whips through the menus. WiFi seems to be the main stumbling point right now, though, which could put a dampener on your internet browsing.
From a usability standpoint, you're probably better off sticking with the native OS on the two MIDs. Still, if you're keen nonetheless, instructions on how to install it yourself, together with the images for download, are available here.
Archos 5 Internet Tablet running Maemo:
Archos 5 Internet Media Tablet running Maemo: