If there are any linux users out there interested in a client allowing them to add tasks without surfing to the web interface, I give you the following piece of code.
First, what it does:
1) when the script is run (I suggest linking it to something like /usr/bin/toodledo, and making a keyboard shortcut to that command), it allows you to enter a task, it's context, it's folder (project), it's priority, and optionally, it's due date. It then uploads it to your toodledo account.
2) if you are offline, no problem, it just writes the task to a temporary file, and allows you to add the rest later when you're online, and uploads it then.
Second, you need to enter your toodledo numeric ID at the appropriate place within the script for it to work.
It is licensed under the BSD license, so do exactly what you please with it (redistribute, modify, sell, whatever).
If you have problems, you can contact me at the mail adress specified in the code, and I'll see what I can do. I won't implement widely differing features, but minor tweaks are negotiable (for free of course, this is a hobby).