I'd not heard of this before it came up on the North Race website (but that is probably because I don't bother with the mainstream cycling websites - I'm just not that into lycra). Personally, I enjoyed my time off cycling over Christmas, but it does sound like a nice challenge. However, I'm pretty sure you have to be young, free and single to cycle 500km inbetween Christmas and New Year; I managed just 35km in my two errand-run trips to the shops.

I wouldn't do that much damage to my knee though, I need them too much.