PRS gather distribute money to songwriters.

There is info on their website here about the scheme :

http://www.prsformusic.com/creators/membership/gigsandclubs/Pages/gigsan...

The Gigs and Clubs Scheme ensures that PRS for Music members receive royalties when their music is performed in UK pubs and clubs.

How does it work?
If a song that you have written is performed in a pub, club, bar, community centre or hotel at more than 10 gigs in the previous year (based on the date of submission), just send us a core set list and we'll pay you for your performances. This includes touring performers, resident performers and DJs.
To qualify your song must have been played at least 10 or more times at gigs or in DJ sets in the twelve month period prior to your submission.
Upon registration, participants are provided with an email template for submitting set list and event information