I just found a great new tool! Twitter user @andymurd has created a mashup that maps where your twitter followers come from and shows them to you in a zoomable map. (Hat tip to @Mashable for blogging about it this morning.)
Go to the Mmmeeja tools page and give it your twitter handle. It will build the map and give you code to embed the map on your own site, just as I have done below. Check it out and let me know what you think!