challenge for artefact

[Mark]

Also re: calling times, I'm thinking 3 hours should be a fair amount of time to write a post. I can see some people that max out the word limit maybe having a hard time with an hour and this will allow people to revise and such. Additionally I think a round length of a week sounds good just so this doesn't drag forever. That's a little more than a day per person so it should be ample. If anyone feels like they need more than that, please say so. Otherwise I think we'll go with that.