I wrote an article on using Flickr to promote your products over on Practical eCommerce:
Flickr, a photo sharing site, can be a powerful tool for promoting your products. Not only can you upload images of your products, where they can be seen throughout the Flickr website, but you can encourage your customers to participate and socialize with your company and products by uploading and sharing their own images of your products… – Using Flickr to Socialize Your Products – Practical eCommerce
There’s been a lot of news lately about companies using Twitter successfully. Sure, you can micro-target an audience which has already told you they’re interested just by following you. But is Twitter really an effective social networking tool?