For what it's worth, I didn't have to whiteboard once during my several interviews. If you're interviewing with new SF or NYC startups, you'll find many of them care far more about practical* skills than pop quizzes. This certainly isn't universal, but it shouldn't frighten you away from trying interviews.

* (not that algorithm knowledge isn't practical, but for a lot of smaller, "web-interface-around-a-database" startups, they're not nearly as important as being comfortable around a full web stack)