The rush tickets for Leopoldstadt, which I believe are only sold in person at the box office, are said to be sold out every single day when the box office opens (many plays which start selling them at 10am can still have rush tickets as late as 2, 5, even 30 min before curtain)... and in my experience trying to get them many times, this is true. I eventually got them by showing up before 10 and being lucky... but I think for a play with no stars, a sad subject matter, a period piece, and written by an old writer who's name isn't even included in the title... I think that's very very impressive. I think it would be fair to have assumed the crowd hungry for this play and/or going to it because of Stoppard's name would be in the non-rush ticket buying category, leaving the rush relatively easy. But it was harder than almost all other major Broadway plays right now to get rush for.