TWFocus - shows your focus, focus's target, and ToT
 

TWFocus is a lightweight alternative to large and complex unit frame mods, if you just want to be able to see your focus, its target, and its target's target at all times.

TWFocus is a great tool for DPS in 5-man instance runs, because now you can
easily set someone as your 'main assist' and see their target at all times.
No more /assist (name) macros!

TWFocus is also handy for healers in and out of raids, because you can set
a tank as your focus, and immediately see his or her health at a glance.
You'll never have to try to remember where your tank's life bar was amidst
a sea of other unit boxes!

TWFocus will show debuffs on your targets. If you're keeping an enemy
polymorphed, banished or hibernated, Focus will show you when they break
free and need to be controlled - and you can just click on your focus
target to pick them up again!

TWFocus supports Clique. Dispel your focus easily, without ever needing to
switch targets!

Updated to 1.4.1. I reworked the way it tries to show/hide the window, so it should only try to show the window at startup time, then fades the window out at any time that you disable it or have no focus.

This was causing conflicts with Xperl.

Notable changes:

* Long monster names with spaces in them should get abbreviated. For instance, 'Boulderfist Shaman' and 'Boulderfist Warrior', which could easily get shortened to just 'Boulderfist...' by the display, would now appear as 'BoShaman' and 'BoWarrior'.

* Casting bars! When one of the focus, focus's target, or focus's target-of-target starts casting or channeling a spell, a casting bar will appear beneath their unit box.

Why's the casting bar useful? Various classes could use it to switch and interrupt a focus. Healers could watch it to know when the focus has begun casting a long, damaging spell, and anticipate damage on the targeted player.