I guess I'm meaner than most; I'm an 8 time Bully, winning 6 of those.
Loss 1Ambassador/Cutpurse/Rabbles with Worker's Villages, Lighthouses and Dukes also important in the kingdom. My opponent had 7-3 Lighthouse split and junked up my deck much more effectively than I hurt his.
That game was in January of 2011; I didn't get Bully again until last June.
Loss 2My second loss, from less than a month ago, involved the thought process "Pirate Ship is bad because it's slow; but if I'm Scheming, I can play Pirate Ship much more frequently, getting its value higher, so it should work much better!" Nope.
Win 1I opened Swindler/Potion, got some Familiars and Scrying Pools, and some Hunting Parties to keep playing attacks.
The rest of my 5 wins were all Ambassador games
Ambassador/Quarry into Bazaar/Wharf plus a couple Rabbles (and one more Ambassador and one more Quarry); 18 to 4 final after 15 turns
Ambassador/Caravan/Ambassador plus a Market, some Caravans and a pile of Throne Rooms; my final deck size was 27 cards, opponent ended with 29 Coppers, 8 Estates and 9 Curses, 69 total cards; 25 to 11 final after 22/21 turns (I was first player and had last turn).
Ambassador/Ambassador into Cities, Grand Markets, a Pirate Ship, and apparently Great Halls when I didn't have big coin hands. Managed to get Pirate Ship to +$6. Final deck size 31 against 23 Coppers/5 Estates/10 Curses/65 total cards; 47 to 27 after 24 turns.
Ambassador/Ambassador into Alchemists, Bishops and Border Villages. Also an Island, a couple Markets, and a bit of IGG action. Opponent was pretty heavily Bishoping, this game was a bit closer and I didn't get my milestone of fewer total cards than opponent's junk cards. 28 to 23 after 22 turns.
Ambassador/Hamlet on 5/2, but the presence of Peddlers made that awesome, as I bought no Silver, eventually picking up all 10 Peddlers (I had also grabbed my second Ambassador on turn 4). I also got some Margraves for draw (plus additional attack). 31 total cards against 16 Coppers/5 Estates/9 Curses, so 31 vs 30 there, just missing my milestone. 19 to -4 after 17 turns.
Ambassador is probably my favorite card
*note: FWIW I don't know the levels of my opponents when I actually played them, but the current levels of my opponents in those Ambassador games are 26, 2, 0, 14, and 32 respectively. I'm currently level 35, my max was 39, but I've spent most of my time sitting in 33-35.