Nothing -- not even a treat -- gets Ace as excited as a kitty cat, but most of those he has met have been behind glass.

Today, as we walked down Light Street in Federal Hill -- after a stop for lunch, a visit to the new Doggie Style pet boutique, and some shopping at the hardware store (also dog-friendly) that bears his name, Ace encountered this friendly feline, perched atop a giant cushion in the window of a home.

Usually, upon spotting a cat in a window, Ace will jump up and lean on the rowhouse it's in for a better look, upon which most cats either arch their backs and hiss, or run off.

This one, though, was at street level, and the cat was up for some play. It pawed the window, rolled over and stretched languorously on its cushion -- not the least bit frightened by the big dog head looking in.

Maybe it was high on catnip, mellowed out on sunshine, or groggy from listening to too much classical music -- or perhaps just bored with that non-moving, gold-crown-wearing black frog that shares the window.

But this I know for sure. Every time Ace passes that window from now on, whether there is a cat in it or not, he's going to get excited and look for it. He never forgets a window.