I went on ebay.co.uk the other day, when I saw a Compact Flash (CF) memory card, that can be used as a hard drive in an Amiga 600 (and Amiga 1200). I bought two CF-cards, one with AmigaOS installed and one with additional 2200+ games).
And yes, there is also hard drives for the larger models (A2000, A3000 and A4000), but this is not the time now.
Note: If you want to buy a Compact Flash hard drive for your Amiga, I recommend buying it from Rob (finestcomputers) in Hungary. Partitioned, formatted and only 2-day delivery – life does’nt get any better that this.