Well, one of my males was very lazy.
He was a big fat black and white rat named Pipin, that I tried to train but he would have none of it.
He just lazed around in (or on) his little wood house and just sorta peered around at the world. I did get him to be able to walk with a leash though.
Now my other rat, a big cinnamon brown one, Merry, on the other hand, was super friendly, super trainable, and very very energetic. Every time I'd step foot in my room, he was up and scratching at the cage to be let out to see me.
He was very well trained...he learned his name and would come when I called for him, he would sit and ride around on my shoulder (I always called him my "Pirate Ratty"
), I could let him walk around the house wherever he pleased but when I had Pipin on the leash he would beside me like a dog at heel, and he was even litterbox trained.
*sigh* I miss my litle boys.