The Saints Blog (no, not these Saints, go here for a priestly perspective, there!) at SPQN has a post on twins (or related to twins) who are saints.
Why strike my fancy? I have an identical twin* in Iowa (of all the corny places...)
Also, there was a set of identical twins in seminary for Detroit, I think they might be ordained now.
One of our seminarians (at least) is a twin as well.
And I saw a set of twins being carried into the penance service last night.
* My first weekend in the seminary, he showed up with his girlfriend (now wife) in tow, bout got me kicked out!
* At my ordination, everyone kept asking him why he wasn't in clerics and with an alb on. 'Seriously, I AM NOT HIM!!!!'
* My first weekend in the parish in my first assignment, I mentioned: 'If you see me around town with a girl, it's not me, but my twin brother.' Yep, got that disbelieving look; until they showed up at the festival five weeks later.
* He gets me back when I visit him, in similar ways.
* Best one yet, he and I were together in Iowa, he was wearing an 'I'm the evil twin' t-shirt (I was in civies), the waitress didn't get why it was so funny that he was wearing it, not me.