I'm with William Morris on the subject of conference swag - "Have nothing in your houses that you do not know to be useful, or believe to be beautiful".
If you stretch the definition of beautiful to include fun, that seems like a pretty good rule of what stuff people should give away from conference stalls.
I don't go to conferences that often, but every time I do, I'm reminded of how unsustainable the whole thing is. People create mountains of cheap plastic tat to give away to people who go past your stall, with the aim of making them remember you.
Even from a marketing point of view, it doesn't make sense to give away junk. Unless people keep and use the thing you give them, you're not getting your message through to them. If people see your thing, think it's crap and throw it away, you're creating a negative association between your company and some useless tat.
A lot of people who go to trade shows and conferences love any swag, and will rush to the stalls as soon as they open to excitedly get as much "Free stuff!" as they can. But how many of them will actually buy something as a result?
There's so much junk out there that will end up on landfill sites, so many t-shirts that you'll never wear except for painting, so many stress balls and useless bits of tat.
The other end of the spectrum is stuff which is obviously not cheap, and that the people on the stalls don't want to give out to every passing punter, or stalls who have one expensive thing to give away to raffle winners.
So what makes a good piece of conference swag?
Some colleagues took some branded kazoos to a conference recently, which I think just about fits into the category of "useless but fun".
Pens and pads are always a good one - who doesn't need more pens? I stay in hotels a lot, and I judge a hotel by the quality of its stationery. The best swag I ever got was a fold-up bag from WebVisions
The PHPStorm stall at DrupalCon Portland was a very good one - they had the lot.
- Something useful - a keyboard shortcut cheatsheet.
- A T-shirt that I've actually worn (admittedly not out in the street)
- Something useless but fun - a branded yoyo.
The only problem was that they weren't going to make a sale from me, because I've already bought the product. Having said that, it's strengthened my mental connection to them, my licence is coming up for renewal, and the next upgrade sounds pretty good...