An interesting post at Science News addresses the costs of conferences. All sorts of issues arise, including shrinking travel budgets, environmental costs of all that air travel, preliminary work that becomes "permanent", and even the number of trees used to generate program books. Having been in the biomedical science biz for 20+ years now, I have survived several waves of "let's quit meeting and just do this online." Conferences will never go away for one reason: we like them.
Oh, I hear people complaining about taking time away from their work and family. We all gripe about time spent in airports. Yet we all keep submitting and accepting and going because nothing replaces face-to-face interactions for us human beings.
There is value in meeting potential colleagues and reviewers. Some of the best ideas and collaborations get built around informal conversations when you toss a group of people with something in common together. Big keynote addresses could just as easily be done via the net, but those do not keep me on the road. No, it's the chance to meet new people who will help me think about things in a new way. I always consider a meeting successful if I get one new idea to explore.
Last month my department had a panel discussion about working a meeting, directed at our trainees and junior faculty. Those of us on the panel all agreed that networking (there's that word again) was why we paid for attendance. You never know who may be important in reviewing your work or getting you hired sometime down the line. Even if you really only connect with other trainees, you will learn more stuff about what other programs are like (you may be in nirvana and not know it). You may meet someone who will be hiring when you are ready for a second job. You may meet someone who will be reviewing you on their first study-section assignment. You will learn something from everyone you meet. Think of it as being mentored by a hive of "E-Bees".
There are some tips we gave our n00bs to make their networking easier. First, get a professional non-university email. You do not want all your job offers and conversations going through your university accounts. You also do not want to use an address that is too personal; "email@example.com" or "firstname.lastname@example.org" will not impress potential colleagues. If it does, you probably do not want that job. Figure out some permutation of your name and/or science and get that gmail account set up now. As someone who recently changed jobs, it was wonderful to have a "permanent" email to use as my university account went dead.
Next we suggested business cards. Even in the age of the electronic frontier, the humble piece of dead tree remains the most accepted method of exchanging contact information. You're a trainee and they don't make cards for you? Do it yourself! Anyone with a computer and printer can buy a pack at the office store and have reasonable cards in less than an hour. Yes, some people will exchange cards and then throw yours out in the airport. Some new acquaintances will put you in their contacts. That's the way it works. You will do the same.
Finally, consider starting an online presence. If you aren't up to a full-fledged website, at least start on LinkedIn (this link takes you to my public profile as an example). The networking site for professionals essentially puts your resume into your profile. Upload a nice photo of your face, and you're in business. Eventually, you will make connections on the site. Some of us even get the odd job offer via LinkedIn (wrong place, wrong time, but otherwise something I would have jumped at). It will not yet replace emailing your CV, but it does give you an online presence that should not provide any embarrassing personal details. Eventually you will find useful information here via interest groups and discussions.
Finally, remember that the real meeting takes place away from the microphone. Casual discussions in hallways and restaurants and bars are more important than plenary sessions (unless you are on the platform, and even then...).