I want to see some pics of what some of you have done. I'm interested now... Barrel in the bucket? sounds neat. I'm also envisioning my bucket, with some sort of funnel mounted onto the cutting edge.
For the chute idea, you can build a frame out of wood and nail corrugated tin to it and make a makeshift extension chute.
By the time I go buy cement, put the cement in the mixer, mix it, pour it in a wheelbarrow, move the wheelbarrow and dump it, the thought sets in "why didn't I just order redi-mix..." But then then I go do it again.