While he'll always be known as the star and co-creator of the greatest television show about nothing, comedian Jerry Seinfeld has been enjoying a healthy post-sitcom career, relishing the lower profile that's come with his back-to-basics stand-up. Hardly embodying the same petty, moral indifference and nihilism of his on-screen alter-ego, Seinfeld is a talent when it comes to observational humor, offering a unique take on the minutiae of everyday life, incorporating it all into a successful act that makes little use of obscenities and low-brow crudity. Before catching his reunion with the “Seinfeld” cast on the upcoming season of “Curb Your Enthusiasm,” take the opportunity to watch Seinfeld in person at the Landmark Theater on Saturday, Sept. 26, at 7 p.m. $45-$75. For tickets call 646-4213 or visit www.ticketmaster.com. — Mike Hilleary