Assesment Center - business cards?

Hi Mike, Mark and Wendy,

Listening to the 2 podcasts on Assessment Centers, I have a follow up question.

For an external assessment center where a number of candidates are invited and activites (group work, etc) discussed in the podcast are conducted.

Should I bring my business cards of my current employer to help me stay in touch with the assessors and the other candidates? If so, what can be done to stop other participants from telling my current employer that I am participating in another firm's assessment center? 

I'm asking because assessment centers seem to be different from traditional interviews where you meet only a few people. When meeting many people outside hiring managers and HR of the assessment center company, what are the rules? 

Thanks,

Tony