We all have our favourite game system but what qualities earn it this prestigious rank for you? For most, it's probably the quality and/or range of titles available, pure and simple. Generally there are many game developers to thank for this but every now and then one appears who goes on to release a succession of high-quality titles on a particular system to such an extent that they alone become a major reason for owning said system.
Two examples I remember well are Ultimate for the Spectrum and Team 17 for the Amiga, but the period that stands out most for me was that of Rare, ironically the modern incarnation of Ultimate, and their run of releases on the Nintendo 64.
In the eyes of many, Rare's releases for Nintendo's black slab, whilst not always particularly original, were so consistently superb that they even eclipsed those of Nintendo themselves. I'm not sure I'd go quite that far myself but they certainly contributed a great deal towards the success of the N64 and my enjoyment of owning one. They released more than ten games for the system in total; none of them sucked but these are my five favourites:
5. Diddy Kong Racing (1997)
4. Jet Force Gemini (1999)
3. Banzo-Kazooie (1998)
2. Blast Corps (1997)
1. Goldeneye 007 (1997)