The Great Eighty Flash Fiction Competition comes from Third Word Press.
It is a free to enter, biweekly competition.
The prize is £20 cash and publication on their website. If your piece is chosen for publication in their anthology, you will be invited to join their fundraising initiative: to promote the anthology across your network and sell as many copies as possible. You’ll receive royalties on the anthology. The idea is: for each anthology you sell, you will subsidise the printing of 3 anthologies for the homeless to sell across the UK, providing an income for homeless people.
Check out their website for further details.