For most people, money isn't everything. They need enough to "survive" (a very subjective term) but that's about it.
Definitely, if a company can't afford to pay a whole lot, and they can't offer good stock options, you're limiting yourself quite a bit. But as long as you can pay enough, you can probably pull in talent with other things.
Some ideas that come to my mind are:
A mission that people can believe in. People will take a pay cut if the job they're doing supports something that they want to support. I, for one, took a job that offered 15% less than another one because I would be helping to cure/treat cancer instead of working for the DoD. It made a difference that my mother had just passed away from cancer. I suspect Khan Academy has a good chunk of this.
The experience over the money. I, for one, would work for free to be able to work directly with somebody of the caliber of Steve Jobs. People will take a big pay cut if they will be able to grow personally and professionally while they're at the job.
Cheap but valuable perks. There is a whole host of things that you can provide that give more value than their dollar amount. Free coffee, soda, flexible work hours, not ever expecting overtime, and lots of time off are just a few.
Getting people who are good enough, instead of the best. I don't particularly like this one, but no doubt, companies have made it work. If you don't have a lot of money, perhaps instead of getting the best, you settle for people who can do good enough. This may be more effective when the people are doing something that isn't a core part of your business than ones that are. Nobody likes saying that they're settling for something less than the best, but you're also less likely to attract top talent when you have little money to spend.