In no particular order...
Music videos with trains in:
Bloc Party, I Still Remember.
I don't know why, I just like trains. Also, the music video for Fur Patrol's
Precious, because it kind of freaks me out every time I watch it.
Ferret racing Archive.org, which hosts the prelinger archive. Hundreds of ephemeral movies, ads, health videos, social guidence. My favourites include:
Peversion for Profit (c. 1965), which teaches us how porn can weaken our resistence to the communist threat, and also turn our sons and daughters into lesbians.
Personal hygiene (c.1950), in which a soldier learns how to keep clean with the power of folk-songs and the support of his comrades in arms. This support includes scrubbing him clean in the shower.
Cindy Goes to a Party (c. 1955), which teaches us how passive-aggressive fairy godmothers can be.
Are you Ready For Marriage (c. 1950), in which we learn that being as thick as two short planks doesn't mean you shouldn't get married, just that you should wait a year.
Music you kind of have to dance to and that sounds good in summer, like
Send my love to the dancefloor, I'll see you in Hell (Hey Mr DJ) or
Clothes off! The fact that I finally finished uploading all the episodes of QI
series 1, series 2,
series 3 and series 4 as mp3s.