A second site, Mojungle, is currently for sale on eBay - the auction ends on December 14th. Starting bid: $60,000. As mentioned previously, Mojungle lets you post cellphone photos and videos to your social networking profiles via an embedded widget. I actually like the service, but if you’ve been following Mashable over the past few weeks, you’ll know they face more competition than ever before. Minor rivals like Abazab, Umundo, Supcast, Nakama, Kindfish and FotoDunk (recently acquired by iLike, despite having zero traction on MySpace) are small fry when you consider that MySpace Mobile and YouTube Mobile are ramping up. What’s more, social networking will be pre-installed on mobile devices if companies like Oz succeed in their aims.

So where does that leave the add-on sites? In previous instances (YouTubeYouTube for video, Slide.com for slideshows, Photobucket for photos), add-on services have had time to build critical mass before the social networks were able to roll out their own products - the mobile startups just haven’t achieved that. But while Mojungle might not see massive success as an independent company, an existing service could certainly buy it to save building their own mobile service. And there’s still an opportunity to build it out as a blog/MySpace add-on, but that window is closing fast.

While we’re on the subject of sales, note that ScriptMimic is being sold, only a few weeks after I covered its launch. Anyone else?