The 5 points you list above sum to something greater than just those points. It's like a huge funded, connected marketing machine of experienced hackers. Camaraderie is an interesting point; in YC it's very easy to get everybody "on the same boat." YC invests in you, you deliver. They work for you, their investments, you work for them, your vision. The guys next door are also in the same situation. It's actually like a moderately sized company running parallel production pipelines. This setup is difficult to replicate because not only do you need the right people, you need the right money, and the right money and the right people.
Which means to do something similar, you cannot lack any of the points (wonders how Techstars and Highland are planning). Consider holding events (remember mydreamapp.com?); gathering a dozen or so beta-stage teams from here should be enough to throw something noticeable. A gallery kind of function, or project profile sorting by category and such, might also be good high-priority tasks. After all, your hosted teams are looking for investors/buyers.
I'm not really trying to replicate YC. As you mention, there's already Techstars, Highland, and YEurope for that, and any attempt to replicate YCombinator runs up against the fact that they're simply better at what they do. Heck, even if this site was successful, I'd still probably prefer YC funding.
However, YC doesn't scale. So there are hundreds, probably thousands of other startups out there with worthy ideas that won't make the cut. Simply because it's a numbers game.
Some of those are going to start up anyway, and probably apply either to a later YC round or to local angels. That's our plan, for our "real" startup. But many more of them will give up because they think nobody's watching and nobody cares. I don't think that's a reflection on their character, I think it's the rational thing to do. Thing is, everybody loses out because those startups don't get started.
So the goal here is to provide an environment where the 90% of us who don't get YC/Techstars/YEurope funding continue with our startups, and have something we can show local angel groups. As I understand it, the main problem facing angels is they're afraid founders will give up and send the angel's money down the tubes. This would give founders a place to develop and test their ideas in the critical probably-a-flop-but-could-be-useful stage before taking it to an angel.
I sat around feeling bummed for about an hour, read some of the forum posts, and then decided that there was something I could do about the situation. As I see it, there are 5 main reasons to go to yCombinator:
1. Money. The $15k or so that yCombinator gives can be useful for some people.
2. Connections. They're very good at making introductions to investors, and give you instant credibility.
3. Advice. They've been through the startup experience before, and have seen numerous startups succeed or fail.
4. Marketing. "A yCombinator startup" seems to get instant attention on certain venues, particularly with the influential early-adopter market.
5. Camaraderie. I suspect that a large amount of the success of yCombinator startups is simply due to having a bright, passionate peer group, all going through the same experience. Some of PG's comments have suggested this too: when groups have worked off-site they "looked like the plant that just didn't get the miracle gro".
I can't do anything about #1 or #2. I'm hungry for #3, but there are other sources of information out there. Get a few dozen people that are starting or have started companies together, and a few are bound to know the answer you're looking for. I can do something about #4 and 5, and that's what inspired this site.
This is basically a place for startup founders to show off their work, get quality feedback, and then release it for the world. When you register your startup, you're randomly assigned to a group. It tries to put startups in the same city together, though there's a random factor so you don't end up with 7 startups in one city and 1 by itself. (In the future, I'd also like to add the ability to pick your group.) If you have not launched yet, all your feature announcements - and the existence of your startup at all - will only be visible to your demo group. Once you have launched, they become public for everyone to view, letting you gain some publicity.
I was inspired by organizations such as the Grameen Bank and the Harry Potter fandom. The Grameen Bank lends money to groups of people, never to individuals themselves. This produces strong peer pressure to repay the loan. Similarly, it's much more difficult to give up on the startup dream when you'll be letting down the 7 other startups in your group. When I add karma, there'll be both a group component and an individual component, fostering a sort of "coopetition" between and within groups.
As for Harry Potter - in fandom, there's a "social price" to membership. You have to write fics. When you join, people want to know what you've written, and they want you to comment on the stuff they've written. Similarly, the hope is that the social price here will be that you keep pumping out features and gaining users. The site is open to anyone actively involved in starting a startup: the one requirement is that you do things and don't just talk about them.
There's a lot more I'd like to add to this site: karma and stats are high on my priority list, as is Markdown for comments and announcements, and it could use a bit of a UI makeover. I'll try to keep up on feature requests and bugfixes, but I do have a day job, and this is a side-project aside from our main startup. Please bear with us; this was done on a very tight timetable (2 weeks from rejection to site launch), and hasn't had too much testing.