Okay, this is pretty sweet.
About a year ago I took advantage of Second Life's "Parcel Media" support to build an in-world map browser of TravellerMap.com in SL. This basically just sets the media URL of a parcel (a chunk of land) to a map URL, and built an object that is textured with that media URL, along with controls to pan and scale the map. Here's what I came up with:
(I'm that attractive sea creature, by the way.)
Today I got a link from Corro Moseley pointing me at another in-world build by Daden Limited:
I believe it supports multiple map sources, not just TravellerMap.com, and wow is that integration nice. Look, look! I'm standing on Utoland! Look at the text board in the upper left corner - it's showing the RSS feed from this blog, and you can click to read articles!