It's a tradition to have a gift-exchange evening at out ESF-tournaments on Thursday night. Those tournaments start on Monday and have the finals on Saturday. Since we have umpires coming from allover Europe, we always give something from our home-country. A fellow umpire from the Netherlands always give "Stroopwafels", two waffles with honey in the the middle. I mostly give away a key-ring with a pair of wooden shoes ("Klompen").
(See for examples this site: Hollandwinkel.NL - Sleutelhangers, magneetjes, etc. - Geschenken en souvenirs)
From Italy I got once a bottle with Italian olive oil. From the Czech Republic a bottle with Czech beer, a German federation beer bottle opener. The very best I've received was from a Greek umpire: A softball, still in plastic, from the Olympic Games in Athens...
Lanyards are very popular right now. Even our national federation gives them away in orange with "klompen" attached.
At the Indoor Cup at Schiedam, every January, are also some USA-umpires present. Then we exchange gifts as well. Several coins, pins and T-shirts I've received from USA-umpires.
I think this tradition should be kept alive. It gives you things to remember the different tournaments you worked on...