Last year (2007), many projects were all about "Web 2.0", which is a phrase I hear far too often. When they're talking about it on the evening news, you know it's already over.
A while back, I did some work with the now defunct relaXSEO.com on microformat code. Microformats are the Next Big Thing, at least for a while. To learn about them, look in Wikipedia for starters and Google Social Networking. Those two things should keep you busy for the next week or so.
One of the more popular pages on relaXSEO that I coded makes tags for Technorati, IceRocket and de.licio.us. It generates xFolk microformat html that can be copied and pasted into a blog entry to provide the tags that those services want to see. The xFolk Cloud and Tag Generator is my version of it; same code with different defaults. It also generates the code to make a moving Tag Cloud of those same tags.
It generates the code that makes this display: