I have happily used the great Single Click for a long time, but some time ago decided to write my own wrapper around UltraVNC. Main reasons for creating it, were that I needed Aero support (which wasn't available when I started this) and wanted it to be extremely simple and give it a somewhat better look. It comes with an builder tool, which I name Digital Dutch Remote Support Builder. It is free for everyone, including commercial usage. Limitations are: Single ip, No encryption and no repeater.
The Digital Dutch Remote Support Builder looks like this:
Fill in the fields and click "Build Remote Support Tool" and you will get Remote Support Utility which works like Single Click and looks like this:
More information and the download can be found here:
http://digitaldutch.com/remotesupportbuilder/