O'Neil has collaborated with a diverse community of friends and advisers, scoring theatre productions and short films, playing improvised shows, and working with dancers and painters. Her previous bands include Rodan, Retsin (with Cynthia Nelson), The Sonora Pine, The King Cobra, and Drinking Woman. She has played live and on recordings with Mount Eerie, The Naysayer, Come, Mirah, Ida, Sebadoh, Jackie-O Motherfucker, K., Michael Hurley, Papa M, and Amy Ray. she has released several albums as Tara Jane O'Neil, formed the Ecstatic Tambourine Orchestra, and crafted soundtracks for film and theater.
O'Neil is also a notable visual artist. Her work has been exhibited in New York City, Barcelona, Tokyo, Kyoto, Louisville, and Portland, among other places. Her artwork has appeared on her solo record covers, on the record covers of many others (Retsin, Ida, The Naysayer, Castanets), in poetry books by Cynthia Nelson (Raven Days and The Kentucky Rules) and Maggie Nelson (cover of Something Bright, Then Holes), in the magazines Punk Planet, Magnet, The Wire, Venus Zine, Copper Press, and various international publications.
Who Takes A Feather, a book of her drawings and paintings, was published in 2004 by Map Press out of Tokyo. In 2007, Meridians. A Blighted Bestiary was published by Yeti, including an album of live recordings, 4-track demos, and out-takes. O'Neil starred in the 1994 indie film Half-Cocked as herself, credited as "Rhonda".