Software to handle 100/1000 hours video?
After reading about FCP's 1600 track, 558 day long sequence test I don't think that's the limit of the software, but the hardware: "...very large numbers of clips within FCPX will slow the machine down."  

Same is true of Adobe's Premiere - as the project grows, the performance lags. Avid Media Composer manages media differently and AFAIK, there's no limit (?) to the sequence length, but in the comments of the FCP 558days/1600track article, someone writes, "Last time I built a sequence over 13 hours, Avid stopped playing audio." Again, that might be a hardware and/or configuration issue.

Possibly Sony's Vegas would also be a contender?

Not sure about Blackmagic Design's DaVinci Resolve or EditShare's LightWorks (both free).

------EDIT
After talking to some Avid editors, I think I may be wrong and that Avid doesn't like projects even 24hr long, more like a 12-18 hour limit. Not a lot of day long content getting made for broadcast I suppose!

------EDIT
Interesting - &amp; so much for what I think I know - Avid's sequence length maximum is comparatively quite limited. From a friend, "At 48KHz, about 12 hours. The limit is 2,147,483,648 audio samples. Six hours if you work at 96KHz."

------EDIT
Don't have an Avid setup to test on, but of note, I understand that if you remove audio tracks, Avid sequences can be much longer. This may hold true for other editing applications &amp; worth testing if you only need 100 or 1000 hours of just "video" and no audio.