Hmm. Post-uni, I can only think of a couple of friends I've made, and only one I'd call semi-close (as in, we think on similar wavelengths about a lot of things and enjoy each others' company). The others are more friendly acquaintance, occasional playdate, don't discuss certain topics friends. All through my quite small church.
However, post-uni I've rekindled a lot of friendships with people I only slightly knew at work or uni years ago. So they're new "friends", but not "new" friends, you know? Two of my closest friends are from my old job, working at the movies - one also went to uni with me. We were friendly at work, but now we have a weekly singing group at my house, watch movies together and go together to the few shows my city ever has. I'm not really a super-best-friendy, Sex In The City BFF-type person; I doubt I'll ever be a bridesmaid, and if I ever feel the need to weep on someone's shoulder it's DH's, not a female friend's... but these two girls are pretty cool and we get along really well. I can see us being there for each other if one of us got cancer or something, you know? (Morbid much...)
So yeah, if there's someone you liked pretty well from way back, but didn't get close to because you were in different life circumstances, too busy or whatever, you could try to reconnect. In some ways it's easier than starting from scratch.
ETA: I'm now also quite close with DH's two best guy friends, one of whom is actually living with us at the moment. We have a fortnightly poker game.
They're all single, love my cooking and enjoy DD, so it's cool. They and my two girl friends are geeky, which helps - I have a hard time being friends with non-geeky people. Even if we really like each other, we tend to run out of things to say.
I reconnected with one friend at another's wedding because we were both pregnant - we got along really well during our pregnancies and birth, but once the immediacy of child-having was gone, we really didn't have much to talk about. Which is fine, but not terribly lasting, you know? Sometimes "nice" just isn't enough to sustain a friendship!