Introduction: Knex Crane Capeble of Lifting 3kg
It doesn't have the looks but gets the job done. I used a pulley system and a lot of gear wheels. (I didn't use to much gear wheels otherwise it would go very slow.) On a simple electric engine. Sorry but i am not going to post this, trust me making a crane like this is much more fun by your own. It took me to make it about 8 hours to get it up to 3kg.
I also made some other instructables.