Question
How can we reuse concrete sidewalks by breaking it up into irregular  pieces for a path?

Answer
Here is one person's adaptive re-use of broken concrete to make a path:

http://www.leknott.com/photos/path/index.html

They placed it like flagstone, then filled in the voids woth decomposed granite...and it looks nice, too.

I have used it to make garden steps, informal stairs up a slope, borders, and as a stacked wall with mossy plantings.  It is a good re-use of material that would otherwise fill space in a dump.

Unfortunately, too much of a good thing can be overwhelming...especially if you live on a smaller parcel.

Plus, it can be tough on the hands - wear gloves!!  In my younger days, this oversight cost me some stitches.

If you need more suggestions, try a google search for "recycled concete", or something similar. Or, I can throw some more links at you, if you'd like.

Marc