[10] She also took a role in a Fleet Bank commercial,[11] and appeared in a Red Cross Campaign benefiting victims of Hurricane Katrina.

She has played multiple lesbian roles: Shane McCutcheon in The L Word; Rosie's (Drew Barrymore) partner Jilly in Everybody's Fine; Candace, the lesbian lover of Sophia Myles' character, in Art School Confidential; and Lena, a press agent who works for Liev Schreiber's character, in Ray Donovan.

In April 2006, Moennig made her Off-Broadway debut as "American Girl", opposite Lee Pace, in Guardians by Peter Morris.

[16] In 2007, the Hetrick-Martin Institute (HMI) produced the documentary My Address: A Look At Gay Youth Homelessness in cooperation with Moennig.

Directed by Gigi Nicolas, the documentary explored the experiences of homeless gay youth and the work of the HMI.

Moennig was an ambassador for the brand,[20] appearing in the launch video and designing a limited edition pair of boots.