One of the nicest things I got as an engagement present was a gift certificate for a manicure. With everyone looking at my hands, I really appreciated it - and since my friend and I both worked in Downtown New Haven, she sent me to Panache.
They're really professional, fast, and friendly enough. It was a pleasant experience, and the hand massage, always a pick me up, was particularly refreshing. I've since been in a couple of times, and while I'm not dedicated enough to call them "my" nail place (I dabble at others, particularly if I see a bargain here or there), I like them enough to buy gift certificates there for friends.
(They'll also cut your hair, but you can do better)