lately I've been having this weird problem. The mouse arrow would for no apparent reason, begin moving diagonally from the right of the screen to the bottom left. This happens regardless if I am using a mouse or the touchpad. Sometimes the way to stop it is to unplug the mouse (if one is attached), or wait for it to settle down at the bottom left corner of the screen. Trying to move the mouse arrow while it is going on it's little joy-ride feels like swimming against a tide. Its really annoying especially if I need to show my supervisor something and the arrow decides to act up..
A colleague has the exact same machine but with Xubuntu installed, and has never had this issue.
p.s. I'm running Unity 14.04 on a Toshiba Portege Z30a notebook.
Edit: output of xinput:
⎡ Virtual core pointer id=2 [master pointer (3)] ⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)] ⎜ ↳ PS/2 Generic Mouse id=11 [slave pointer (2)] ⎜ ↳ USB OPTICAL MOUSE id=13 [slave pointer (2)] ⎣ Virtual core keyboard id=3 [master keyboard (2)] ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)] ↳ Power Button id=6 [slave keyboard (3)] ↳ Video Bus id=7 [slave keyboard (3)] ↳ Power Button id=8 [slave keyboard (3)] ↳ TOSHIBA Web Camera - FHD id=9 [slave keyboard (3)] ↳ AT Translated Set 2 keyboard id=10 [slave keyboard (3)] ↳ Toshiba input device id=12 [slave keyboard (3)]