Security B-Sides and Neighborcon Las Vegas were great events. They happened because of the people who put them together, those who pitched in to help, and the people who participated -and- because of individual and corporate sponsors who made a lot of the niceties possible (beer is a nicety, right?).
When the idea was first floated, Astaro was eager to help get things rolling, then more sponsors joined in. One of the other early supporters was WiKID Systems, there's a great post on their blog explaining why they sponsored, their reasons are very similar to my reasons for enlisting Astaro's help.
Head over to the Security B-Sides Las Vegas wiki page and check out all of the people and companies who helped make these events a reality. And thank them if you get a chance. Even if you aren't in a position to "buy one of each", follow the links, check out the companies and see what they do- maybe even take a few minutes and send a "Thank you" email to the companies. Believe it or not, companies do not sponsor events just to get people liquored up (OK, maybe IOActive does this occasionally)- a little appreciation will go a long way towards helping get sponsorships for future events. Yes, there will be future Security B-Sides events, keep an eye on the B-Sides website for details.
By the way, this applies to more than just these events. There are a lot of demands on personal and corporate finances, especially in this economy. A little gratitude can go a long way towards keeping you supplied with great security events. And free beer.