Networking follow up...months later

[EvilLlama]

So I'm a really shy person.

I attended SIGGRAPH over the summer and met some really interesting people. I sent out follow up emails to most. I kept in touch with about two of them.

Networking fail.

There are two people in particular that I wanted to keep in touch with, but they're really advanced in their careers and I couldn't think of anything to say that didn't sound annoying noobish. Kept using the "I'll do it first thing tomorrow" excuse and now it's 3-4 months later.

So my questions are:
1)Is there any drawback in trying to reestablish that connection now?
2)How frequently should you touch base with people you meet at conferences?
3)A lot of networking sites suggest to follow up with something useful, but how could I as student provide anything useful to a Creative Director?


Searched online for advice, but most of it is geared for people applying for jobs or are businesses. In the future I'll want a job, but I still have 3 semesters of school left to go, so right now I just want to stay in contact.