There was some recent discussion in another thread about grinders for corn. Rather than further hijack that thread I am starting this one specific to the topic to add my $0.02.
Except on occasions I am away from home, I eat something made from cornmeal I have ground [most typically cornbread] almost every day of the year. What I have been using for many years and highly recommend if you are serious about grinding frequently is a commercial coffee grinder of the type you see in grocery stores where you select and grind your own beans. There are two major companies which dominate the market for this type of grinder; Bunn and Grindmaster. All of my experience has been with various Grindmaster models. These things were built to last and are easy to maintain. My first acquisition was a Grindmaster model 500 which from the serial number was made in the mid 1930's. It still runs fine though is not my "daily grinder". That would be a model 875 which is only a few decades old. Current models include the 810, 835, 850, and the 875 among others. These 4 models differ only in the hopper capacity and all share the same motor and grinding mechanism. Interestingly the burr set in my 1930's model 500 is exactly the same as in these four current models though the grind size adjustment mechanism differs. If desired, it is possible to sharpen the burr set though this is not done in the commercial space where new replacement burrs are installed instead. . All that is needed is a cordless dremel type tool with a diamond coated grinding disc, a vise, and a couple of hours. The potential for sharpening the burr set is why I have stuck with Grindmaster vs the Bunn as what I have seen of the Bunn burr set design it would be more difficult to attempt to sharpen. There is a model 890 Grindmaster that has a different burr set design that also looks more difficult to sharpen.
Somewhat counter intuitively, the grinder draws more power with sharpened burrs than with unsharpened ones. The throughput increases even more though which results in a reduction in Whr/lb. Specific numbers for this. My Model 875 as received required 37 seconds and 8 Whr to grind a lb at my usual grind setting. Post sharpening it required 19 seconds and 7 Whr per lb. My usual grind setting is one click stop courser than espresso.
These grinders can be had very cheaply relative to their new prices. Restaurants, coffee shops, grocery stores go under on a regular basis thus making these available. These things are heavy! I've seen some go on ebay for less than the cost of shipping. I just now scanned the "completed" listings on ebay and saw a model 850 sold for $0.99 for local pickup only. If you are a bargain hunter you likely will do best with a local find.
Pictured below [photo harvested off of web] is a Model 875 and a pair of 835's. The models 810, 835, 850, and 875 look fairly similar but differ in height due to differing hopper capacity.