Ooh, Good luck at RU this weekend! I'm an undergrad there now... with whom do you want to work?? I'll give you the inside scoop on faculty & grad students.
I've applied to 9 cog psych/science/neuroscience PhD programs and have only been invited to one visitor's weekend so far - Univ. of Maryland, College Park.
The other 8 include:
MIT
Princeton
BU
WUSTL
NYU
CUNY
Columbia
UCSD
Where have you applied??