OSM give real prizes!
Despite being an open source/data community rather than a business, OSM has in fact rewarded at least one volunteer with an actual weeks Caribbean holiday (provided they did some mapping while they were there):
Quote from http://wiki.openstreetmap.org/wiki/Osmfieldwork_Press_Release
"OpenStreetMap, the Wikipedia-like website which is mapping the world, is sponsoring one of its volunteers to go mapping for a week on the idyllic Caribbean island of Antigua - an idea sparked by Ed Parsons of rival Google Maps.
At last year's State of the Map conference in Limerick, Ireland, Ed spoke about the recently-launched Google Map Maker, Google's process for getting the public to supply map data for them. The countries initially covered by Map Maker included many Caribbean islands, leading Ed to express sadness that fieldwork was not involved.
This off-the-cuff suggestion, and a spirit of friendly competition, caused Gervase Markham, an OpenStreetMap contributor, to set up a pledge on the PledgeBank website. People pledged to improve OpenStreetMap's coverage in the Caribbean themselves by tracing over available aerial imagery, and to donate £10 each towards sending one lucky mapper on just such a field trip.
74 people, including Ed Parsons himself, signed the pledge, raising £740 to fund the expedition in order to significantly improve the OpenStreetMap data. One name from the pledgelist was chosen by a verifiable random process - Steve Chilton from Middlesex University, UK (who happens to be a professional cartographer, and is the driving force behind the look of the default cartographic styling for OpenStreetMap). The OpenStreetMap Foundation will be sponsoring him to travel to Antigua from 5th to 12th of June to add GPS traces, classify roads, and to add road names and points of interest, building on the work already done from aerial photos by the pledgers. He expects the weather to be marvellous.
"I am really looking forward to this fieldwork trip", said Steve. "I have contributed data to the map in many parts of the UK, and it will be great to contribute data in the Caribbean and add another little bit to this fantastic global project."