Today my church is running an ambitious sponsored event: our organist Keith Pigot has come up with 12 hours of repertoire and is playing from 7am-7pm in aid of the repair and restoration of our organ. I went over to hear him fairly soon after the start and he was going strong; I’ll return at lunchtime to check on him and give out mulled wine and mince pies to those who’ve come to hear him.
I’m happy to report he reached the £2000 target at about 10 this morning but all further support is welcome: donate at Organathon. Or of course come along to the church in person today and hear the performance! 
We would really like to make our organ into a proper recital instrument and not just repair recent damage from falling plaster.
I once organised a similar event in aid of RAG at university: 12 hours of hymn singing. But it wasn’t all done by just one person!