411 REFERENCE · Wikibooks
Chess Opening Theory/1. d4/1...e5/2. Nf3
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
2. Nf3 - Reversed Alekhine
This move may seem like a good response, and also is similar to Alekhine defense but from white side. However black can just push the pawn further and force the knight to move (if you don't want to lose it of course).
Black's responses:
2... e4 - 45%; winrate 47% (w) - 50% (b)
2...exd4 - 35%; winrate 50% (w) - 47% (b)