Every year since 2006, the good folks at iA have released a web trend map (2007, 2008). It maps the biggest online trends onto the Tokyo Metro Map (PDF). If you spend far too much time on the web, love maps (especially transportation maps) and appreciate finely crafted information design, the web trend map provides hours of fun.
This year's map is no different. Actually, it is different. If you buy the printed version of the map, you also get private account on the new Web Trend Map website. With an account, you can create your own web trend map to track the trends, websites and people that interest you in real time.
Matthew Solle, one of the organizers of London IA, has created a London IA Web Trend Map (shameless self-promotion: I'm on there).
And it's not just useful for tracking London IA people.
Want to learn more about fonts? There's a map for that.
Want to know what's up with the tech community in San Francisco? There's a map for that.
Just need some inspiration? There's a map for that, too.
(Sorry, I couldn't resist.)
I'm particularly excited that iA is planning on introducing RSS for Web Trend Maps. This means I should be able to replace entire folders in Google Reader with a single, curated feed.