Are there any startup showcase websites?

The web is full of gallery websites for CSS design. e.g:

• http://www.css-showcase.com
• http://www.cssmania.com
• http://www.awwwards.com

http://startupli.st/ just recently launched and appears to fit the bill.

I've also used...

http://www.killerstartups.com/ http://www.feedmyapp.com/ http://www.startupnorth.ca/ (if you're Canadian)

Depending on the type of startup, there's likely niche related sites.

I suggest doing a google search for your competitor, look who's linking to them, and submit to the same sites. A search would look like:

link:www.whatever.com

What about http://www.new-startups.com/

We recently launched, & would be more than happy to feature your startup on http://99Launch.es.

Another one I just found: http://appmit.com/