Flickr.com is a rich resource of ideas for photo themes. One Flickr feature worth checking out is Flickr Groups. Groups are areas on Flickr where users post photographs that relate to a common theme. One example is the Geometric Beauty group. This image from KrystiAn pAn.K's Flickr site is a good example from the Geometric Beauty group or "pool."

Here's another great photo from the same pool from Toetap's Flickr stream.

Here are some of the more interesting groups:

• B&W
• Catchy Colors
• Frame Within a Frame

You can participate in groups created by others or create your own. Here are some guidelines for managing a healthy group and the Flickr Groups FAQ.