I am not sure if that what it was called (pretty sure it wasn't "Taxcaster") but there was a great online version of Turbo Tax that in a single page asked for most of the income and credit items that the desktop version does, then gave a very close estimate of your taxes.
I used to be able to use it to quickly see what my tax impact would be if say, I sold stock and took some capital gains or made a donation and took a credit.
The page looked a lot like TT Desktop itself (Taxcaster doesn't) with all the categories for income and credits on the left with the same colors and iconography as the desktop product, and the running tax total on top updating automatically as you entered or removed data.
Did that get moved or renamed? Or is it gone forever?