I agree with Rork and Wolfsnap, macro with the F4 works like a charme.

Just bought me a used Novoflex bellow and a 12mm Extension tube.
With my 24mm lens reverse mounted it gets me down to aprox. 7:1.
Still waiting to get the first film back.

AFAIK, you'll need a 12mm extension tube to mount the bellow on all modern Nikon AF cameras,
for sure for the F4 and F5.

A cheaper way is to use extention tubes, a reverse adapter (BR-2A) and a good wide angle lense.
here are some test shots with this gears:

http://t-bernt.de/Foto2/macro.jpg

If you just want to shot macros up to 1:1, a good macro lense will do the job,
even the Sigma and Tamron macro lenses gets good reviews.

cheers
Thomas