All tips mentioned here have been applied to my HP 520 laptop, using Hardy Heron.
- Changing default boot option- edit /boot/grub/menu.lst
- Using Nokia phone as a usb EDGE modem- see Shihab's Blog
- Location of downloaded packages- /var/cache/apt/archives
- Change options to "Open With" menu- edit ~/.local/share/applications to add/remove .
- Update Firefox. Fix "Offline Mode" at startup bug.
- VLC Media Player skins directory- ~/.vlc/skins2/
