Many of the tools we have utilize multiple ground sides.  As you page through the photos on this site, look for them.  

The first gallery (click image to display) has small to medium sized slate finger and hand tools.  The tool pictured below is a nice triangular handadze with a palm-over style used for chopping.  This handadze is the only tool I have had authenticated due to the cost associated with microscopic use wear analysis.

Here is a tray of slate tools from the Groups and Pairs gallery.  Check out all of the straight ground sides.

The fingerholds and handholds on these slate tools are more comfortable than you would expect.  

Next is a gallery of three nice small mudstone finger tools.  All are 3 1/4" long.

Here's a 5 1/4" scraper (silicified mudstone?) with ground sides all the way around.

Here are three more finger tools with ground sides.

Here are two galleries of medium-sized ground-side sandstone hand tools. 

Here is a quartzite gallery with some nice ground sides.

 

 

Ground-edge stone tool use has been around for 35,000 years. (link opens new tab/window).