Nick: this almost warrants another 'list' (sticky) thread???
As for me, not that i usually play for scores (As odd as that sounds), but my only recollection is on Stellar Wars, 3 ball, 666,660. (no pix sorry).
I was bummed out that it wouldnt go to 666,666 but then realised the points only increment in 10's not 1's ;-(