Next, a playlist of boos from Audioboo. These are all 2 minutes long, except the one that's 3 minutes long.
And finally a playlist from YouTube. The 3 tracks at the time of writing are 3:51, 3:43 & 2:35 long.
And there you have it, a little under 25 minutes of sounds all gathered together in one convenient post. Hopefully there's something there for you to enjoy.