[kirillzubovsky]

Search for sites like http://betali.st and put up your splash screenshot. People who are interested would check it out and try the product.

Post facebook/twitter messages to your followers and ask them to try. Better yet, find some twitter hot-shots who might be interested in your product and send them a tweet. Sure most will ignore you, but if 1/10 tries it out, you've got another power beta user.

Lastly, take a look at my post here (http://www.geekatsea.com/what-google-must-learn-from-my-fail...), will give you some ideas as to what beta users say vs. what they mean.

Good luck!

[kevinchen]

…and then after you get one of those "hot-shots" testing your product, create an artificial scarcity by doling out beta invitations slowly. [Of course, this will only work if you set up some kind of website with pretty / cool-looking screenshots.]

[bunturedempter]

You can check out http://wikindu.com as well, It's not betali.st but you can send your completed startups. maybe after you get out of beta, you can submit it to wikindu.com