diff --git a/functions/utility.zsh b/functions/utility.zsh
index 1cfaf1a..1af3902 100644
--- a/functions/utility.zsh
+++ b/functions/utility.zsh
@@ -1,39 +1,42 @@
+# Lists the ten most used commands.
 function history-stat() {
-  history | awk '{print $2}' | sort | uniq -c | sort -rn | head
+  history | awk '{print $2}' | sort | uniq -c | sort -n -r | head
 }
 
+# Makes a directory and changes to it.
 function mkdcd() {
-  mkdir -p "$1"
-  cd "$1"
+  mkdir -p "$@"
+  cd "$argv[-1]"
 }
+compdef _mkdir mkdcd
 
+# Changes to a directory and lists its contents.
 function cdll() {
-  if [[ -n "$1" ]]; then
-    builtin cd "$1"
-    ls -lFhA
-  else
-    ls -lFhA
-  fi
+  builtin cd "$@"
+  ll
 }
+compdef _cd cdll
 
+# Pushes an entry onto the directory stack and lists its contents.
 function pushdll() {
-  if [[ -n "$1" ]]; then
-    builtin pushd "$1"
-    ls -lFhA
-  else
-    ls -lFhA
-  fi
+  builtin pushd "$@"
+  ll
 }
+compdef _cd pushdll
 
+# Pops an entry off the directory stack and lists its contents.
 function popdll() {
-  builtin popd
-  ls -lFhA
+  builtin popd "$@"
+  ll
 }
+compdef _cd popdll
 
+# Gets ownership.
 function gown() {
   sudo chown -R "${USER}" "${1:-.}"
 }
 
+# Reloads ~/.zshrc.
 function reload() {
   local zshrc="$HOME/.zshrc"
   if [[ -n "$1" ]]; then
@@ -42,18 +45,39 @@ function reload() {
   source "$zshrc"
 }
 
+# Provides a simple calculator.
 function calc() {
   echo "scale=4; $@" | bc -l
 }
 
+# Displays human readable disk usage statistics.
+function duh() {
+  (( $# == 0 )) && set -- *
+  if [[ "$OSTYPE" == linux* ]]; then
+    du -khsc "$@" | sort -h -r
+  else
+    du -kcs "$@" | awk '{ printf "%9.1fM    %s\n", $1 / 1024, $2 } ' | sort -n -r
+  fi
+}
+compdef _du duh
+
+# Prints columns 1 2 3 ... n.
+function slit() {
+  awk "{ print $(for n; do echo -n "\$$n,"; done | sed 's/,$//') }"
+}
+
+# Displays user owned process status.
 function pmine() {
   ps "$@" -u "$USER" -o pid,%cpu,%mem,command
 }
+compdef _ps pmine
 
+# Finds files and executes a command on them.
 function findexec() {
-  find . -type f -iname "*${1:-}*" -exec "${2:-file}" {} \;
+  find . -type f -iname "*${1:-}*" -exec "${2:-file}" '{}' \;
 }
 
+# Serves a directory via HTTP.
 function httpserve() {
   python -m SimpleHTTPServer "$@"
 }