Fan funds were developed as one way to provide closer links between various national or regional science fiction fandoms. They achieve this aim by providing the funds for a well-known fan from one country or region to attend a major science fiction convention in another country or region. The funds exist solely through the financial support and generosity of fandom.
Most fan funds are ongoing, with fans competing for the privilege of taking a trip and other members of fandom voting for their preferred candidate. Fund winners become administrators of the fund until the next winner returns from a trip. Fund winners are expected to publish a trip report.
The "big three" intercontinental funds — TAFF (Trans Atlantic Fan Fund), DUFF (Down Under Fan Fund) and GUFF (Get Up-and-Over Fan Fund) — and some others such as FFANZ (Fan Fund of Australia and New Zealand) are bi-directional in alternate races. Other ongoing funds, such as CUFF (Canadian Unity Fan Fund) and NAFF (National Australian Fan Fund), take a fan from one region to wherever the relevant convention is during that year.
Still other funds are "one offs" that raise money to bring a specific fan to a specific convention. For example, the "Tucker Bag" fund brought Bob Tucker from the U.S.A. to the 1975 Aussiecon, and the Bring Bruce Bayside fund enabled Australian fan Bruce Gillespie to attend Corflu 22 and Potlatch 14 conventions in California in 2005.
See also the Fan Funds tag: http://fancyclopedia.org/system:page-tags/tag/fanfund