We've got Webhook on kickstarter right now. It's a static site generator with a CMS.
https://www.kickstarter.com/projects/1749618880/webhook
Definitely did it for validation. While it's awesome that we hit our goals and have some early customers for our product on Day 1, it's going to be tough to re-attain those users and get them on a monthly subscription once we launch. My guess is we'll lose over half of them. That's mostly because we're using an outside channel (kickstarter) to take payment. Also, I'm sure there will be some people that just don't think the product is what they thought it to be.
What KS did do was give us a very easy way to validate the product. We're self-funding and basically said... hey, if we can't raise $20k, this project likely isn't worth investing more time and money in. Granted, we were hopeful, and even assumed we'd do better, but that's the way we looked at it. It's basically fail fast with a real timeline. Sometimes (and I've done this before) you can get emotional about a product and not walk away.
Running a KS campaign is also a small preview for the marketing you'll need to do for the actual product once it's launched (example: a post like this). You go through some peaks and valleys and have a 30-day roller-coaster ride. If you end up funding your project, even if it's a small amount, that's a great feeling of "win" that can carry you through the first few months of your project. Small teams need some early wins to keep positive.
I highly recommend it as a replacement for seed funding for software companies. We'll likely end up around $40k when we end. That'll break down like this.
1. $2000 for video.
2. $4000 in fees.
The other $34k will let us operate for a few months as if we were making decent revenue. We'll also likely invest more of our own money into the idea now that we know it has an audience. Now it's just up to us to deliver on the promise and sign up our customers.
One tip I'd give to people thinking about KS. Keep it simple. You don't need to give Tshirts and stuff. If you're building software, just build software, don't do anything that will take away from you doing that.