I was really in to Lego when I was young, especially the so called "Technical Set".
My first Technical Set lego was the blue racing car which Mum and Dad got me for my 7th birthday.
Next for Christmas I got the Tractor (I was very upset though because I had clearly asked Santa for the "Big Car"! - shown below)
The next one I got was the Crane, I can't remember if this was a birthday or Christmas present, but the crane was probably the coolest technical set lego of the day (apart from the Big Car of course).
These two are the Forklift and the Helicopter which I didn't get, but I was able to build both of them from the parts of the other sets, plus some "supplemental sets" I got which are collections of spare parts. In fact I was able to build the Forklift in yellow, red and blue :-)
This is the "Big Car" - the king of Technical Set Lego in the late 70's!!! I was never able to build this because it required four of the big wheels and I only had two from the tractor. The Big Car had a full gear changing mechanism.