Now when you install cabinets, everything needs to be level and straight, which means if you have wavy walls you must shim the cabinets (put small pieces of wood behind them so everything winds up straight). This will leave with a gap.
In my case, the gap was barely noticeable in some spots, but in others were closer to an inch...if not wider. Fortunately, it's not something you notice...especially since I don't have a backsplash. But the problem is, things fall in between the wall and counter more often than you'd think.
First I thought I'd buy a piece of laminate and cut and glue the appropriate pieces necessary to cover the gap. That was before I realized a sheet of laminate was almost $50. Then I had a blast of inspiration. Backer rod, aka Caulk Saver.
Basically, it's this foam that you shove into big gaps and caulk over. This way you're not using a tube of caulk every five inches. Here is one of the smaller gaps behind the counter...see, not so noticeable, just very annoying.
I didn't take any pics with the caulk in, because it's still drying. If you have to use the ginormous amounts of caulk I did, it'll probably take a few days to dry. Use clear...unless you're able to find another color caulk that'll blend into your counter.
As for the inch plus sections of gap, I used foam pipe insulation. I cut it in half, tucked it in and caulked right over it. This whole easy fix cost me around $10 of material I already had. Definitely cheaper than the laminate and involved a lot less work and time on my part.