What the heck, people already know my profession. It's not a masterpiece but two students did it for me at the end of a lab session that I had been supervising so it has a sentimental value for me.
If you can understand at least three jokes without checking them up - you da physicist! (Even though one of them is technically a math joke)
My favorites are top left and top center. Priceless :D Cat in a bra, heh, heh :D
The gold thing in the background is a silicon wafer with chips, it's a reference to my specialization (nanoelectronics).
Nerdy, isn't it? :D
I feel stupid for not being able to understand your desktop background. :(