I've been thinking a bit about "value added" taxes, which are a substantial source of revenue in many European countries, but not in the United States. The "value added" of a company is essentially the revenue it takes in minus the expenses it pays to other companies; equivalently, it is the profits of the company plus the money it spends paying its employees.  The total production of the economy is then the sum of the "value added" by different economic units. If markets are competitive, the price of a good is the cost of producing it, and a 20% value added tax translates ultimately to a 25% increase in the final price above the other costs of production; for example, if XYZ corp sells widgets for $3 a piece, with $1 in capital costs (including depreciation), $1 in labor costs, and $1 for inputs purchased from ABC corp, and ABC has no suppliers, then (if supply is inelastic) a 20% VAT tax raises the final price to $3.75, of which $2.50 is value added and $1.25 is paid to ABC; XYZ thus pays 50 cents per widget in taxes, and ABC pays 25 cents per widget in taxes. It is hoped that the reader will see (or trust) that the result is similar when supply is elastic.
Because of the argument given, the VAT is typically viewed as equivalent to a consumption tax; it gets collected along the supply chain, but is equivalent to, in this case, a 25% tax applied at the end. At the risk of being wrong — and, note, that is well in the spirit of this blog — it seems to me that a 20% tax on corporate profits combined with a 20% flat income tax on the workers is also equivalent. If corporations are paying a 36% tax and workers are paying a 20% tax, replacing that with a 20% corporate tax and a 20% value added tax with no income tax seems likely to be equivalent.
There is always, with tax policy, the question of true economic incidence of taxes, which especially in the long-run is likely to be independent of legal incidence; one of the reasons a lot of people like corporate taxes, and a lot of wonks don't, is that it is officially paid by companies, and it's not entirely clear who the actual payers are. (Some quick searching pops up this 2005 working paper on the subject; my recollection is that recent research is unable to exclude, insofar as the question is well-defined, the proposition that about one third of it is borne each by the shareholders or owners of the company, the employees of the company, and the customers of the company, though I don't have a source for that; it probably would depend on the industry, and of course over the entire economy consumers and employees and shareholders are not remotely mutually exclusive groups.) Possibly because of my American bias, or the fact that I'm just not in that sort of literature generally, I haven't to my recollection seen much analysis of how much of a value-added tax actually falls on consumers, ultimately, and how much is absorbed by someone else.
As with many economic concepts, it gets rough around the edges, so that the first definition I gave is not entirely "equivalent" to the second. The money a company pays to a company providing its employees health insurance wouldn't be subtracted from "value added"; that's part of paying your employees, only in-kind. Is the money spent on air conditioning for your office an expenditure on externally-produced inputs or an implicit labor cost? A reasonable argument could be made for the latter, but I'm sure it's never treated that way. Whatever the definition of "value added", the tax base for the value added tax is typically closer to the former definition than the latter, so that a company pays "value added tax" on exactly that portion of its revenue on which no other company is paying "value added tax".
The age old confusion about percentages rears its head here; the upshot is that the tax is 20% of the cost with taxes and is 25% of the cost without taxes, so e.g. an item that ends up costing $5 includes $1 in taxes and $4 of "other".
To keep things simple.
Here's where perhaps it's worth emphasizing again that in practice the two definitions given previously for "value added" are effectively very similar.
On the corporate side, $1 before taxes becomes .8×.8=.64 cents after taxes, just as without the VAT.