Two things that will increase the number of site visitors dramatically:
1) A Chrome extension that simply links to the website (can be made in notepad in 2 mins). I'm sure it will rise to the top of the Chrome Web Store. I would make one myself but when you come to publish it, it needs to verify that you're the site owner. Here are a few tutorials on how to make it:
http://goo.gl/eEX4r4 http://goo.gl/WnFU7o https://goo.gl/xbGvwJ
2) Allowing users to login with their Facebook/Google+ accounts. As soon as the user logs-in, prompt them to share the website with their friends (which will eventually generate a chain reaction on social networks and jump from one users profile to another). I think this is not easy to make and will take a while but it will drive the number of users trough the roof. ;)