The T.R.A.F.F.I.C. Domain Industry conference will be in Vancouver, British Columbia on June 8-10. This is a long running and very authoritative meeting within the domain investment industry, and is billed as a great way to learn the business side of domains. You can read the official announcements here or some press coverage here. I have been to several of the TRAFFIC meetings, and consider them to be among the best conferences I have attended overall, especially when it comes to making connections and learning the real behind-the-scenes business aspects. Where search marketing conferences are often a lot of fluff and filler, these meetings are very much true-grit business gatherings.
Vancouver is a beautiful city, just under an hour from the US border north of Seattle. Amtrak runs 2-4 trains per day between Seattle and Vancouver, direct from downtown Seattle to downtown Vancouver (a few city blocks from the conference hotel).
To cross the border and return hassle free, you need a passport plus driver license or other ID, or one of those new enhanced driver licenses (Washington State offers one) or a Nexus pass which gives you a fast lane through the checkpoint (read the tips about usage).