Dawbs, something similar happened to us a couple of years ago. The original Star Wars Trilogy had come out in a new DVD box set right before our anniversary and I was totally psyched that I finally had a good gift idea. I even ordered it from a weird web site, Sears.com, because they had a special coupon. Not Amazon, not Best Buy, but Sears.
The day that it arrived, there were two boxes from Sears. Thinking it must have been a shipping error, I opened both of them. (But carefully, just in case.) Dh had not only bought the exact same set for me, but on the same day from the same site. I put it back together and put it in his mail pile.
When he got home, I had the one I bought hidden behind my back. He handed me the box and said, "Well, you've already kind of seen it so you should open it now." I said, "No, you open yours!" He looked at the two identical boxes and said, "But mine is Star Wars." "So is this one!" "But I got a special discount at Sears.com." "So did I!" I call it our "Geeky Gift of the Magi".