Conferences and Conventions

I'm starting to think about writers' conferences and convenions (and similar events)...  I have never before gone to one.  I have always wanted to go to "Bloody Words" - the one and only mystery fiction convention in Canada (usually held in Toronto).  For years, I just couldn't make it, but this time I'm in!  I've already registered and paid, and I am really looking forward to it.


But what about other conventions and conferences?  I know there are several that pertain to crime fiction, held in various milieux around the USA (Bouchercon, Killer Nashville, Sleuthfest, Left Coast Crime, and so on). 


I recognize  that conventions can be a lot of fun and a great way to network or to meet fans.  However, some of them get rather expensive, especially if you plan to attend more than just one or two.  Besides the enrty fees, there are also travle and lodging expenses, plus plus plus.


On the other hand, perhaps the connections made, or the sales generated, or the word of mouth created make it all worthwhile.


What are your own experiences with conferences and conventions?