最近換了11.04，發現Alt+Tab無法切換窗口了，用以下方法可以解決。
參考：http://blog.163.com/aravarcv@126/blog/static/1238427282012450133734/
一：確認配置是否正確
-
- Press ALT+F2
- type “gconf-editor” (without quotes) and press Enter
- Go to /apps/metacity/global_keybindings
- Find Cycle Windows//這個地方說錯了,應該是 switch_windows
- 在裏面輸入<Alt>Tab
- Change the key value to (you’ll need to press Enter)
rm -rf ~/.gconf ~/.gconfd
press alt+ctrl+backspace , and logout修改win鍵，例如修改show_desktop 爲 Win+d
* gconf-editor
* /app/metacity/global_keybindings
** show_desktop<Control><Alt>d --> show_desktop<Super>+d