There's basically three options. You spend an outrageous amount of money to expose your site to an outrageous amount of money (think a superbowl ad) so when th

There's basically three options. You spend an outrageous amount of money to expose your site to an outrageous amount of money (think a superbowl ad) so when they feel like sharing our browsing sad stories they'll think of your site. You find out a way to specifically reach your target market by finding out what they like to do and show up there. This is (usually) less costly but more work since you'll have to find out where they are and what they're doing (i.e. google queries, visiting blogs, being in communities (forums), behaviour patterns for targetting by facebook or google, being in specific physical locations, etc.). You think of something ridiculously witty that spreads through communities and exposes your name to many people by word of mouth. I'd say if you're short on cash option 2 is the only affordable option. If you play it right the only significant cost can be time (i.e. visit all colleges in your area and hang up posters). Note that your question is exactly the reason people apply to HN and try to get VC money. All three options are significantly more powerful with large amounts of money and in most cases make or break your startup.