Photos of vintage cassette tapes is the perfect website. It collects high-resolution images of analog tape cassettes and presents them neatly for your enjoyment. (As blogged here at least once before, there's also Vintage Cassettes, which has high-resolution images of analog tape cassetes in their original packaging). Now do VHS tapes!

For me cassettes were a thing of early childhood and have a precise aura: one part read-along kid tapes, one part 8-bit computer games, one part top 40 carefully taped off the radio.

As an analog format cassettes were awful (20kHz?), but used perversely as a storage medium for modern digital streaming codecs I expect they would deliver functionally identical quality to Compact Disc and a far greater capacity. But then again you can just burn hundreds of MP3s to CD and modern CD players will actually play those, so that trick isn't particularly meaningful.