I've been thinking about this for a while and I'm starting to wonder if putting all my stock images on flickr might actually be a good idea.
The images remain small and pretty much useless for publication on flickr, but the search features and what they call Interestingness may actually be a good way to get a photo seen by a potential buyer.
Sounds reasonable. I'd only be sure to put watermarks on the flickr images, they might be taken for web use. The small files make up a significant percentage of my total sales - on micro stock that is. If I remember well you switched to macro, I don't know if different file sizes have different prices there.
There's always the chance someone will see something they like. That being said, most of the entities searching through Flickr are looking for people who are giving up their rights for no money. So unless it's really a great shot that they're really got to have no matter what, I don't think you're gonna get much business. However, you might want to copyright register them all on a cd. Then if some company decided to use them without your permission, you'd have them by the short hairs. ;)
