At work, it's a 14" Macbook Pro (probably a 2011 model, not quite sure) with two external monitors. I use an external apple keyboard, because having a 10-key is really helpful, but I use the trackpad since I have to span 3 screens with the cursor, it's a pain to use a mouse sometimes.

At home, I have a 13" Macbook Air, the previous generation. I prefer using this to be honest than my 3 monitor setup at work since it's light weight, and I am more portable. I don't use any accessories for it, except I did buy a Microsoft Bluetooth mouse that I may use occasionally, but it's primarily for when I'm doing presentations.