I doubt links from any of these sites would be considered bad by the search engines (i.e. you wouldn't get penalized). If the link they provide is rel nofollow, or a 302 redirect - which they often are - they aren't going to help you very much though. Of course you can get indirect benefit if people following these sites decide to link to you from their blog or something. This has happened to me for even a very niche interest website.