Actually, DAT was developed for data backup, concurrently with the audio use. This is why things like filemarks only take up 4 bytes of tape space, as opposed to something like 100k on 8mm exabytes.

I did see a discussion somewhere about 8mm being very bad design-wise due to tape pinch angles or something technical like that, and DAT was much better thought out - also 8mm was originally just for analogue video (with PCM audio), data only came along with exabytes.

Yes, my DATs are very rarely used now, but a TCD-D3 was what I used to use in the miata before the mp3mobile ;)

Hugo