Well, the Retro Computer Dag took place yesterday, and after 3+ hrs of public transport and a couple delays, I arrived there about an hour and a half after it started, and surprisingly there were still a few deals to be had. I'll make a post in the small score's thread later on with my finds.
Overall, I thought it was pretty cool, first video game/retro computer event I've been to in a very long time, and also the first one here in Europe. It's nice seeing lots of retro games and computers all in one place, even though retro computers dominated most of the tables. The main thing I missed, though, was the chance to really trade anything. It seemed more of a flea market with the majority of dealers being from on- or off-line gameshops, with pretty high prices. There were also collectors showing off their collections and recently released homebrew(?) games, but these were all for computers or pre-NES consoles, so it didn't interest me too much

A few avid collectors were also selling games at great prices and were cool to talk to, so that was a definite pro.
Going back to the main con, though, I was surprised how it felt too much like a flea market. The only other gaming meets I've been to in the past were Bay Area swapmeets (I think that's what they were?) in California, and those meetings were more social gatherings where everyone brought a carload of trade/sale stuff...mostly for trades and socializing. I expected something similar here, and also took one very large and one smaller bag filled with trade stuff to the event yesterday, but didn't get rid of any of it - just carried the ton of extra weight around all day

It would have been great if there was something like a trading corner for people to unload their bags and look through each other's stuff - hopefully something they'll look into for next time

It was pretty nicely organized, though, with lots of arcade cabs on free play to test your gaming skills on, and it was also great to be able to put faces to a lot of Dutch collectors! Definitely worth going
