Sony has opened up digital pre-orders for a pair of PS4 launch titles on PSN and the Sony Entertainment Network online store.
PlayStation's Twitter account announces PS3 owners now have the ability to reserve PS4 digital downloads of Crytek's free-to-play shooter Warframe and SCE Japan's action game Knack.
Knack is listed at $59.99, while Warframe is of course being offered for free.
It's a bit perplexing why Sony chose to offer pre-orders for a microtransactions-based title like Warframe, but one would assume committing to it would place a user near the front of whatever download queue might form on launch day.
PlayStation 4 and both titles launch on November 15th.