Jay - I am at a 2.55 myself so I can relate to your situation.
Extra courses are a MUST with a GPA in this range. I would recommend going to a local community college and taking undergraduate classes as a non matriculated student. DO NOT TAKE CONTINUING EDUCATION COURSES.
Take the full class and get undergrad credit for it even though you have your degree.
Recommended classes are: Calculus, Finance, and Accounting or Business Courses.
So far I have completed an Intro to Business Course with an A and I am 80% of the way through my Accounting Class with an A average so far that I expect to maintain.
I keep in touch with the Admission Directors at the 3 schools I have applied to, making them aware of my status after exams and quizzes. To overcome a low GPA I really don't see any other way of going about it. You will also need a GMAT of 80th percentile or better depending on the schools you want. Like rhyme said - if you are going for the elite cluster you will need a 700 or better.
Good luck.
What undergrad did you attend? Major?
I was Econ at Boston University - they are known for crushing their students GPA's so I am hoping that is also a factor, but I let the schools know I am to blame for the low marks and I take full responsibility - making it clear I have matured and am in a different place now.