I speak often. I collect business cards from everyone I meet. I scan them using LinkedIn's Card Munch app. I also automatically collect email addresses from people I send email to.
This has a HUGE amount of value to me.
1. Anytime someone calls I know who it is before I answer.
2. In the old days when Facebook imported from Google it helped me setup Facebook. Same for LinkedIn and Twitter and other services.
3. I often need to contact people I meet. I'm in the people business. Say to arrange an interview with a CEO, etc.
4. It helps me brainstorm who I should call next or follow up on.