Painted Cow Mangler 5000
For about 27 hours, the Cow Mangler 5000 was paintable with team paints. This changed the colored parts on the Cow Mangler 5000 and it used to affect the trail of the rockets (but it no longer does).
There are 13 known instances of this item.
Source
Professional Killstreak Cow Mangler 5000
Team Fortress 2 Level 30 Focused Wave Projector
Paint Color: The Value of Teamwork
Does not require ammo
Alt-Fire: A charged shot that
mini-crits players, sets them on fire
and disables buildings for 4 sec
Killstreaker: Fire Horns
Sheen: Manndarin
Killstreaks Active
No random critical hits
Deals only 20% damage to buildings
Minicrits whenever it would normally crit