Regardless of whether your a politician or a hockey mom, throughout your life, you’re going to be meeting people and building a community around your interests, thoughts, and ideas.
Often, you’ll end up meeting more people then you can keep track of. One tip that I find helpful is to take notes about who I meet. If I don’t get their business card, I try to write down their name and some facts about them in a notebook that I carry with me. I’d highly recommend getting one of those small moleskine notebooks.
Then… I’d recommend using a CRM tool or some type of Contact Manager. At work, we use Salesforce but I’d also highly recommend 37signals’ Highrise. I know some that use Facebook or LinkedIn as the way to keep track of the folks that they meet. The key is use something. Use it to make notes about how you met, their interests, and maybe the substance of the conversation. If you can grab things like their birthday that’s even better.
The key is that you want to be able to more easily recall the data about them when you run into them next time. Sometimes even writing down the information about who you meet and how will help to fuse that into your brain.
One cool thing you can do in Highrise and Salesforce is that you can immediately schedule a followup of somesort. When you meet folks, it’s great to send them a note saying something like “it was great meeting you.” The goal is to keep that level of engagement high.
The next step is… once you’ve made that initial contact, you need to keep them engaged. You need to keep talking to them and have them stay a part of your community.
Oatmeal Stout - Justin Thorp's blog 
Yep, we use Highrise for work related contacts. It’s Ajax UI is very intuitive. They put a lot of attention in making sure it’s easy to key in. It’s rather fast we as well.
I also have a large collection of notes and contact information on my Outlook because it syncs directly with my phone.
Good reminder Justin, totally right about taking notes of people you meet. It’s a great habit to get into.