Update 4th of March, 2016: This script has its own Product Page now and all future updates will be posted there. Should you have any questions, problems or bug reports please use the comment section on the Product Page or the Forum.
A limitation of the StickyHeaders script in version 1.0 is that it is not working in Quick Edit mode. Therefore I updated the script and released version 2.0 which is now also working in Quick Edit mode. You can download the script at the end of this post.
Version 2.0 also eliminates a few bugs that showed up from time to time. While the sticky headers are fully functional in list views, the sticky headers lose their functionalities in Quick Edit mode, but I hope that I can address this issue later (I already got an idea how to do it, so check back a bit later if you need these functions).