So it turns out that the overnight gaps in @lofibeats's YouTube thing is YouTube going into HTTP 429 mode. Presumably the problem is other machines from my VPS provider hammering the APIs, because I can't see my one-request-per-hour causing any rate-limiting problems!
Maybe I should look into using the proper search API, just to be a better neighbor. Google charges money for that though. :(
oh wait looking further into my logs it looks like YouTUbe has actually actively detected "unusual activity" from my bot... which, y'know, makes one request per hour. Oy.
okay, switching to the YouTube data API wasn't that bad and it turns out they give you like 100 requests per day for free. The developer docs fucking suck though, especially when it comes to using an API key instead of oauth.