Buying with BTC is a breathe of fresh air, huh? How about when taxes are due?
If you're a US taxpayer, you are required to report the profit/loss of every single purchase made with bitcoin.
Which means that you need to dutifully look up and record the current price of bitcoin every time you make a purchase, so you can properly report the fair market value, and then copy that information over to Schedule D in the proper format.
And according to the tax rules, if you've made several purchases of bitcoins over time, then you have to separate the purchases into lots. So if you bought 0.3 bitcoin on Mar 1st and 0.2 bitcoin on Mar 31st, and you bought a video card for 0.4 bitcoin on May 2nd, then you have to decide from which of the previous lot(s) you want to take bitcoins on to report the profit/loss at the time when you bought the video card. For each separate lot, a separate line needs to be created (or you may put VARIOUS, and figure the correct gain/loss and just add that to the form, its up to you)
Of course, if its been more than a year between the time you made some of those purchases, you need to separate out the gain/loss into long-term vs short term gains.
And then, if you decide to refill your bitcoin account within 30 days before or after a purchase, and the bitcoin price went down from the time you bought it until the time you made your purchase, then wash sale rules come into play. In those cases, you need to report the sale, and then further mark it as a wash sale, reverting the loss on the form. Then those bitcoins that you sold and rebought have to be put back into your lots of bitcoins to use for further purchases, adding together to the final sale in the future the total loss and gain made by all the wash sales those bitcoins may be a part of (all while respecting the long term/short term gain split).
---
Yea, what a dream! :/