This is a very helpful post; makers should be very aware that there are a lot of costs to producing things, many of which you're unlikely to pencil out when dreaming something up (e.g. 1% of revenue going to storing shipping supplies). This is why so many companies appear to have high margins: money leaks out of businesses all over the place.

To the criticism that Kickstarter isn't about making money: part of enabling people to make things is compensating them enough that they can afford to put in the time.

Nitpick: I think your tax estimate is high, given that pretty much everything else is a business expense, and thus deductible, unless your income is high enough that you have to pay $3K in taxes on roughly $8K in net income (38%: 5% Utah + 33% Fed tax bracket).

Also, you're left with the asset of 800 posters which you're offering for $120/ea + shipping. Sure, you probably won't sell all of them at that price, at least not anytime soon, but you do have to attribute that revenue to the project, since you attributed the costs to produce them to the project, and selling just 10% of them will double your net revenue. (Assuming $130 in revenue each, $6 in transaction costs, $15 in shipping & packing costs, $4 in miscellaneous costs = $105 net per poster sold * 80 = $8400 net pre-tax.)