I have a few decks I'm using:
1) First and foremost, my black/red Hellbent deck based around the Rakdos Guild from the Dominion block, which was released about five years ago. It specialises in getting a large number of creatures, instants and enchantments out quickly, emptying my hand in the process to give some of my creatures additional bonuses.
2) The Angry Kittehs[footnote]It's spelled that way for a reason, not because I don't know how to use the word 'kitty'.[/footnote]: mono-white from Scars of Mirrodin and Mirrodin Besieged.
White Sun's Zenith allows me to put a large number of 2/2 Cats into play, plus I have things like
Titan Forge and
Kemba, Kha Regent to back those up. Also, I can regularly metalcraft due to the number of artifacts I can play with low mana costs. Some of those are equipments to allow Kemba to produce more kittehs.
3) Just completed a mono-red burning deck. It's not pure burn, though, I do have a few creatures that hang around for more than one turn. Still, they all gain bonuses through Landfall or casting an instant or sorcery.
4) Mono-black, not exactly sure what the win condition is. Still, I have a few good rares in there from multiple sets.
Drana, Kalastria Bloodchief,
Carnifex Demon and
Phyrexian Crusader spring to mind.
I've also got a
Sword of Feast and Famine somewhere, not sure where to put it. I'll probably put it in with the Angry Kittehs.