@ShieldsOfWar?!? I've finally found you brother! :P
Jokes aside, I would love to see how a one-shot-one-day roleplay would work. Seems like an ideal that could really cure a problem I've seen in multiple RPs (*Cough* dying off *Cough*). I'd be more then willing to join in, if acceptable. An idea I have, though quite cliche, could include a rag-tag team of adventurers thrown together to sort through an impossible task, let the setting be fictional or realistic. This plot can be possibly character driven, and is definently flexible to time limitations.
I agree I have tried to make a one-shot RP that is fast paced and was done before people lost interest and it succeeded I think their really fun to do on a slow day.
I like your idea but I would also like to chime in. Again it would be cliche but would follow a team of investigators as a super-villain wrecks havoc in San Francisco (like Agents of Shield but not as bad :p) or any other city . The catch is they only have 24 hours to catch him before he destroys the Golden Gate Bridge. Yea I know cliched to hell but I think it would be fun running around the city trying to find the dude also we could out a real 24 time period on it so the RP can be a one-and-done in a day.