American songwriter and actor, composer of Rainbow Connection, who played Koru, a leader of the mathematically minded Qomar, in the sixth-season Voyager episode Virtuoso.
Paul Williams is an American songwriter, singer and actor, an Academy Award winner whose songs include Rainbow Connection and Evergreen.
In the sixth-season Voyager episode Virtuoso he played Prelate Koru, a senior figure among the Qomar, an advanced and haughty people with no concept of music. After hearing the Doctor sing, the Qomar become infatuated with him, and Koru invites him to perform on their homeworld.
The casting was a knowing joke, placing a famous songwriter among aliens hearing music for the first time. The Doctor's fame fades once the Qomar build a hologram of their own with a greater vocal range.