What is your favorite way to quickly raise capital for an investment?

[Jeff Fulkerson]

It's a common story - you come across a deal, the numbers work, and you say "I want to buy that!" You make an offer, it gets accepted, and now it's off the market. You now have 30 days to pay for it.

With the ever-attractive goal of using other people's money (OPM), what are some effective strategies you've used to fund/finance your deals?