Sony's website says the $10 RM-V8A controls the PIP and has TV menu. Of course, it doesn't control many devices. I've never used it myself.

I like the 8-device RM-VL900, but it is $50 and the PIP commands are a bit confusing: Play, Stop, FF, and RW are buttons to work the PIP for example. Without the device in my hand, I can't even remember which does what.