I've written a HTTP Proxy for Mac. nothing special so far, but it's intented to be used for debugging &&/|| development. It features a quite flexibel filter/modifier architecture, a working gui and a non-existant memory footprint. Since I just didn't have the dedication to finish the project but still think there's a market for that, I'd gladly sell it for a fair price. If anyone is interested in just seeing the app (which is unstable), just let me know.