I've just made a map of tags for Photography - StackExchange.
In short: tag size is related to tag popularity and edges are related to tag co-occurrences in questions. Different colors were used for further clarity, to distinguish tag groups, which co-occur a lot.
For me it looks as a (nomen omen) "snapshot" of topics and scope of this SE site. So if you want to you it in any way to promote Photo.SE - feel free!
Also, if you have comments how to improve its usefulness or niceness to the community, I would appreciate them. (Also, any aesthetic pointers are more than welcome - it's not my strongest side.)
- An entry for StackExchange vis competition at Kaggle (please vote if you like it :), it ends on Nov 3, 2012)
- Recipe, code and images at GitHub (e.g. tweak the plot to your taste; feel invited to co-develop)