A very good idea...
I've attended more than a few tech conferences in my career, in many cities...one stands out because of a determined approach by the organizers to encourage "mingling"...
At each meal of the 4-day conference tables in the restaurant adjoining the conference center and breakout rooms had signs placed in the center of the table...each sign had a topic...server-side issues, web dev, etc....
By choosing a table you indicated what was currently of most interest to you, or what you would otherwise like to learn more about...I met a lot of interesting people that I would have otherwise not met...
As most attendees were strangers, blind luck, or choosing a session and hoping to interact with other like-minded individuals in the between-sessions rush presented limited opportunities...
Brilliant strategy, that I've seen repeated only a few times elsewhere...landed a few gigs later on based on info from contacts I met at that conference...