For me, that was the D30, but I had it only for a very brief time as it then got superseded by the D60. My biggest regret - not shooting raw.
Canon EOS D30 250mm f/5.0 1/160s 100 ISO +0.7 EV
Camping in June
Canon EOS D30 25mm f/5.6 1/80s 100 ISO +0.3 EV
Average Yellowstone Family
Canon EOS D30 400mm f/7.1 1/500s 100 ISO +1.0 EV
Canon EOS D30 400mm f/7.1 1/160s 100 ISO 0.0 EV
We were all younger back then...
Canon EOS D30 70mm f/4.5 1/80s 400 ISO 0.0 EV