First off, this is an EXTREMELY simple exploit to level up an alt fairly quickly.
It's also the fastest way to 40, that me and friends have found as of yet. Taking only 30-45 minutes.

Things you will need:

2 people (2 controllers)
One level 40+ profile with TVM unlocked
Access to the Tea Party Guest of Honor quest from Tiny Tina

Method:

Have the player you desire to level stand next to Tiny Tina and activate the quest.
Have the high leveled account go to where Flesh Sticks spawns (he is level 39)
Kill Flesh Sticks, receive the 4,000-5,000xp
You should fail the quest, and have the low leveled character talk to Tiny Tina again.
Do NOT restart the quest until Tiny Tina has gone through the initial sentence of "Flesh Sticks the guest of honor..etc etc" or else it will be bugged, and you will need to reload the game.

I will be uploading pictures shortly, if anyone needs further explanation you can post here or if needed I can show some people how to do this to spread it.

ADDED: DL link to a level 50 siren, for those of you too lazy ;)
-SIREN LVL 50-
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-Assassin LVL 50-
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