QMac 7.10 introduced the Capital Gains Estimator (Under the 'Investing Tools' button, far right of an investing view).
I was skeptical when this was first released, but doing year-end tax planning trades and gifts today, it made life easier than anything else I've done in prior years:
After deciding what basis lots or complete holdings I wanted to sell, it was easy to find the right number of shares of a keeper that shows a LT loss to offset the gain, as you can just type in a number of shares and immediately see the projection. The tax is computed in isolation of other things on a tax return, but it a good enough estimate of net tax.
(I had TurboTax Mac open in with a copy of last year's return, adding the tentative transations to see what the actual projected tax impact would be after all other items in the return.)
I wanted to give some shares of an appreciated security to charity to bump out of standard to itemized deductions. Here, too, the Capital Gains Estimator allowed me to quickly see what the tax impact would have been had I sold the shares and donated cash… vs no tax payable by donating the shares…. however I did have to enter the gross market value to TurboTax to see a projection of the tax benefits… but even that was easy as the numbers were given by the Capital Gains Estimator.
What usually took me an hour or two to sort out and be comfortable with in prior years took less than a half hour including online trades with this new function of QMac.