OK, might as well share a set I've been playing with for a little while.
chunk (Salamence) @ Leftovers
Ability: Intimidate
EVs: 248 HP / 200 Def / 60 Spe
Impish Nature
- Dragon Dance
- Dragon Claw
- Refresh
- Roost
So, I started using this set because I really liked Fatmence's ability to switch in on just about any fighting or fire attacker and win, but I've always hated how passive Fatmence is. I began toying with a bulky DD version instead, which could use those same attackers to set up. This has turned out to be a surprisingly useful 'mon, able to double as a defensive check to a lot of crap and also as an excellent win condition late game.
The basic idea is that you play this like you'd play Fatmence ordinarily, switching this thing in on many of the tier's scariest attackers. In particular you wall things like Heracross, Entei and Suicune well (with Refresh meaning that you don't even care about switching into a Scald or Sacred Fire), which makes this an especially nice thing to have on bulkier teams that have trouble with those three. However, you also have the ability to inexorably set up late-game. Just about every team has something that is utterly setup bait for this Mence, whether it's a Water type that relies on status/burn to check physical attackers such as Tentacruel, Vap and non-Roar Suicune, a physical attacker locked into a resisted move, or just anything that can't break Roost + Refresh (such as Blissey). The Speed EVs allow you to outspeed Mega-Pidgeot at +1 (you deal 65-78% with +1 Dragon Claw, so you have a so-so chance of OHKOing it after rocks damage).
Also, just to give you an example of this thing's bulk, you actually live LO Mamoswine's Ice Shard as long as you remain healthy:
252 Atk Life Orb Mamoswine Ice Shard vs. 248 HP / 200+ Def Salamence: 302-359 (76.8 - 91.3%) -- guaranteed 2HKO
That's NOT factoring in Intimidate, which means that if you've got a couple of boosts under your belt, Mamoswine can't come in and revenge you.
Anyhow, you're obviously walled forever and a day by Fairies, so that's something you'll need to account for in teambuilding. Having teammates that can pressure most fairy types is definitely a must - there's a reason the team I'm running this on right now has three really solid fairy checks. Chandelure in particular has been a good teammate for me, and I plan to use it alongside Victini on the suspect ladder.
I don't have any good replays with this thing (I wasn't originally planning on sharing the set :P), but here's one of it sweeping:
http://replay.pokemonshowdown.com/uu-232588047 - This is why you don't drop Roar for Toxic on Swampert...