Good ole Engie. And just to justify this so-win picture, Machinima has an excellent video on how to play him in Team Fortress 2, including a sequence on playing him offensively. I mean, on offence. He's definitely playing offensively in that shot above.
How to Play the Engineer [Machinima.com, by EvilDaedalus]
Update: Reader Andrew "Duderman" Macintosh (commenter dudenextdoor00) claims responsibility for this picture. Nice job! Original is here.