I can't count the number of times people have offered $100 bounties for implementing some feature or other in Inkscape.
From what I've seen - and I've seen MANY features come into Inkscape from folks who aren't developers - $100 is the wrong way to do it.
Not that people are anti-money or anything like that. Certainly we've gotten rabid success out of our Google Summer of Code projects, but these pay out $4500. So maybe $100 just isn't the right price point to stir interest (even a simple feature is going to require 10-20 hrs work, at which point you might make more flipping burgers!)
In any case, aside from GSoC, I've not really seen that many successful cash-for-code projects in Inkscape.
But I *have* seen a number of similar situations that ended up *quite* successful, but didn't involve money at all.
The Mac port of Inkscape is my favorite example. Inkscape started as a Linux-only product but quickly gained a Windows port. A lot users were also very interested in seeing a Mac port, but few of the active developers were all that interested. I think maybe someone even offered a $100 bounty for it, although I'm not certain; in any case none of the existing developers took interest in doing the port.
But there was one user that was really interested in getting it, and he sat down and hacked away on it. After a few weeks he talked to me and said it was just too frustrating to get something that worked properly and he was giving up on porting it. (IIRC, he was able to get it to build but not cleanly, and when it ran it didn't work properly.)
I sympathized but encouraged him to write up his notes into the Inkscape Wiki, to explain how far he got and the problems he ran into. "Maybe someone else will know how to sort those issues out some day."
Meanwhile, people continued to clamor for a Mac port. Eventually, another person took interest in just doing it himself, and when he asked me about it, I pointed him at the wiki page the prior person had written. This was useful in getting a leg up, and he was able to sort out the build problems the first person had run into, but he eventually also gave up frustrated with the limited results he saw. I encouraged him to update the wiki page with his findings.
This cycle went on for some time, but eventually enough knowledge had accumulated that someone (JiHo I think) was able to clean it all up into a proper procedure, and to start getting successful builds that more people could use. This enabled people to focus on the next layer up - fixing the Mac-specific bugs.
Now there were also complaints that while it ran on Mac, it looked out of place and was hard to install due to its dependence on libx11. People started clamoring for a "Native Mac Inkscape Port". And so the cycle began again...
In Inkscape I've seen this pattern repeated again and again. And not just in Inkscape. This seems to be a universal mechanism for how open source works. I'm sure there's an aphorism or law or something that describes it.
In any case, the lesson that can be taken from this is that if you want to get some feature or fix into an open source project, rather than offering money, have a go at it yourself. Even if it is well beyond your technical ability or time availability, your efforts may be enough to simulate someone else to eventually have a go at it too. This could be a detailed procedure you followed that got close to working but had a fatal problem. Or a messy patch you made that *should* work but doesn't. Or it might be a list of possible solutions you've ruled out and why.
If you think, "I want a way to just throw money at the problem and make it just work," then remind yourself, "Time is money" and throw time at the problem instead of cash. Spend $100 worth of your time banging your head on the issue, trying out ideas and hacking on code if possible, and posting the results even if they turned up negative. They may give someone enough of a clue to stand on your shoulders and reach the goal.
While I hate to be that guy that says "HEY GO READ THIS BOOK!" all I'm going to say is hey go read "Wikinomics" by Don Tapscott and Anthony Williams.
This book deals is about Web 2.0 in its purest form. He speaks on collaboration, and Open Source being the key to success.
It opens up your mind and makes you think in different ways. Bounties are interesting, but they should be a last resort. In that I mean if you have absolutely no other way of contributing, and just that fact that you don't know how to code doesn't count, then "bounties" might make sense. Even then I would still suggest just donating to the OSS, instead of the individual feature.
A Wiki is a great tool for collaboration, it doesn't need to be just about coding it can include features and look/feel of the project. The beauty of OSS is that you can contribute as much or as little as you want, and thats not limited to money.
Needless to say I cannot stress enough the need to read Wikinomics trust me...