diff --git a/.bash_aliases b/.bash_aliases
index 0acfc87..8f4fd8c 100644
--- a/.bash_aliases
+++ b/.bash_aliases
@@ -3,8 +3,10 @@ alias ll='ls -lihF'
 alias la='ls -A'
 alias l='ll -A'
 
+alias t='tree'
 alias sudo='sudo '
 alias grep='grep -n --color=auto'
 alias j='jobs'
 alias df='df -h'
-alias lock='xscreensaver-command --lock'
+alias du='du -ch'
+hash htop 2>/dev/null && alias top='htop'