A few months ago, I spent an hour at Freshbooks, answering questions for a $50 gift card. It was a really interesting session, and the two people running the session did two things right. They encouraged me to think out loud as I explored and evaluated the various screens...

Interesting to learn of your experience. Though not a UX professional, thinking out loud seems an excellent way to do it. I see that usability testing has got a lot cheaper and faster in recent years, with many web sites popping up, offering a variety of testing services, for example, usertesting.com ("get videos of real people speaking their thoughts...") and many others.

Another way for smaller companies to do UX research cheaply (well, cheaper than your $50 gift card) is to go into a coffee shop with a laptop and offer to pay for people's coffee in exchange for them having a go at using your software.