Someone asked me to take some portraits of them soon and I didn't really have a lens that can do the kind of thing they'd want. A recent discussion over at Flickr suggested the Nikkor 50mm f/1.8D as a good lens to get, I picked one up from a store in town for GBP80 which was very very cheap.

I really love this lens, takes fantastic shots, not yet had a chance to take portraits but I love it for flowers as well. Some sample shots can be seen here.

I got the 50 f/2.8 as my first Nikon lens, maybe 8 years ago. Absolutely fantastic lens. I shot a bit on a friends old 1.8 (non-AF). Absolutely fantastic as well.
you've convinced me, that will be my first lens for my new d70