Some useful tricks I just discovered:
cd -
Switch to the previous directory. Example
[root@summer log]# cd /home
[root@summer home]# cd -
/var/log
[root@summer log]# cd -
/home
[root@summer home]#
Ctrl+R : shell autcomplete from history (called "reverse i search")
You then start to type your command and it will autocomplete, then you press Ctrl+R again to cycle between various autocomplete alternatives.