If your biopsies are not too long, you can trim off the sides of your blocks 
and place two or even three ribbons on a single slide, with your intervening 
ribbons on  separate slides. The amount of cutting is the same and it's a 
little fiddly to get used to doing this, but the result is one slide to 
stain, coverslip and file, and one slide for the pathologist to pick up and 
look at. This won't work with larger biopsy specimens but it's great when you 
can do it. My doctors love it cause everything is on one slide. You can mark 
this slide level 1-3-5 and your intervening ones level 2&4