lol, a smidge behind you:
6 (12)-character palindrome address
1LzzzPV9dNbKsk4b6PNaZJTqTm36PzzzL1
Proof:
afe1d9a09ff8e810b1a02eb60609051c85ac37d2a46c6bf9300a457e9e72933a (sha256 of public key, comp)
cool! triple points for the triple zeds
I found a couple more 6 (12), but I suppose the next milestone is now 7 (14) for base58 palindromes
all-number h160s (40 numbers) seem incredibly abundant, so I'm discounting these, but finding leading-letter h160s seems more challenging. so far my highest is 24 with aebecfcecaceafcbefcdfcbb489f7d6aea18934d
32-length base58 seem quite plentiful, but I've found nothing lower yet
I haven't looked at pubkeys, xpoints or real-words yet, but will do soon