Quick answer - 8862 Backhoe. Accidentally came across one.
The following all happened in the space of a year.
It all started by coming across an old dusty box that contained 90% of the parts to make 8862 Backhoe. The set was not mine so I first had to google to see what set it actually was. Next I searched for instructions online and was amazed they were so easy to get. I bought all the missing parts from Ebay (cost a fortune) and finished the backhoe.
I then decided to find my old Lego box that was hidden for about 15 years and remake all my old sets. I then found Bricklink which helped a lot. I remade 8448, 8868, 8459 and 8445. My favorite is 8868. In my opinion the best set released. (hopefully Porsche will overtake it)
I then remade and bought missing parts for my brothers old sets. 8275, 8275, 8284, 8416, 8455.
I was addicted so I then started buying sets on Ebay with missing parts and finishing them. 8880, 8479, 8457, another 8868, 8865, 8432, 8456.
Next I bought some new sets. Volvo loader, Mini cooper, VW camper, Eto-1 and the USC Tumbler.
Now I just need to buy the Actros, the Porsche and some old sets like the Williams and silver champion F1 sets.
I just uploaded my first MOC yesterday and I may start another smaller (and cheaper) one soon. Its been fun