Sooo, we get 2 plots.
Leonard-Pryia: Pryia doens't like Penny haging around cause she's Lenny's ex, and asks him to talk to her. He tries but cna't. Then she bumps into them in a restaurant making Pryia all unconfortable. Penny gets it and says she'll stay away, which Leonard regrets. Sheldon plot: Howard tells Raj he learned a maigc trick, and after preforming it, he leaves Sheldon dazed. Sheldon tries restlessly to figure it out to the point of hacking a supercomuter and attempting to buy uranium. But then it's revealed Howard doens't reallly know the card and the others play along to spite Shel. He never finds out.
Title Reference: Prestidigitation = magic.
Overall: Great episode. Pryia's plot reminded me of Friends when Emily didn't want Ross near Rachel. And Shel's plot was the perfect comic relief to contrast a more serous plot. 9.5/10.