I have quite a few, actually! These first four are hatchmates. Not doing everyone, because I have 100+ dragons, but here are the highlights.
1 of 3 ever, only unexalted.
1 of 4 ever, first of his colors, only unexalted.
1 of 7 ever, 1 of 2 unexalted.
1 of 9 ever, 1 of 3 unexalted.
1 of 16 ever, only unexalted.
1 of 6 ever, only unexalted.
1 of 11 ever, only unexalted.
1 of 5 ever, only unexalted.
1 of 10, 1 of 3 unexalted.
1 of 4, only unexalted.
1 of 11 ever, 1 of 2 unexalted.
1 of 15 ever, 1 of 2 unexalted.
1 of 5 ever, 1 of 3 unexalted.
1 of 11 ever, only unexalted.
1 of 9 ever, 1 of 3 unexalted.
1 of 3 ever, only unexalted.
1 of 19 ever, 1 of 5 unexalted.
1 of 18 ever, 1 of 3 unexalted.
1 of 17 ever, 1 of 2 unexalted.
And there are a bunch of others, actually, but I couldn't look any more. Kaecilius has two ultra-rare sibs in my Hibden.