1. In fact, there is syntax highlighting for all the C-like languages, it's the mode called 'clike'. I guess that label isn't so very fortunate 2. Oh actually, the underlining has been added by me as a means to do author attribution. I should add a checkbox to turn it on and off. Before I had had the text background in various colors but I found that to be an even worse distraction. 3. The keyboard shortcuts are tricky. I'll have to delve into that a bit more (and test across platforms). 4. So obviously for now it's just security-by-obscurity. For now you can take the sourcecode and host it somewhere private. I left out explicit user account management in order to get the first version out the door. 5. Hmm. that's a very interesting thought! It should be fairly easy to build a small command-line tool to upload and download files.
Thanks for the feedback!