Hold'em NL 100

LOOSEST
Two people limp to the button who is shortstacked. He pushes for 26 with AKs. The small blind flat calls the push with three people left to act with T5o. Flop rages, turn 5, river 5. Nihan.

TIGHTEST
Multiway limped pot. Flop comes QTT. MP player bets 3 into 6 or so. LP calls. Turn is a J and MP bets 3 again, now LP miniraises. MP calls. River is a 9 for a final board of QJTT9 and MP bets 1. LP flat calls.

MP has AJo
LP has QTo

Regarding your tightest call...you mean you've never seen a flat call with the nuts before? I have. I can't recall examples but I'm sure I've seen it.

I accidently called with a straight flush once (although it wasn't the nuts). I saw I had the flush, but it was a small one so only called a river bet. It wasn't until after the hand that I saw I had the SF.