LEGO Technic Crawler Crane (8288) for sale online | eBay
Mini crawler crane designed I came up with (cat for scale) I used set 42121 as the base and the instructions for set 8288. The hardest part was setting up the pulley
LEGO 8288 Technic Crawler Crane | BrickEconomy
MOD] Improved 42042 Crawler Crane - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums