There is gossip flying about that United is to resurrect the 'tulip' as a retro scheme, displaying the original Saul Bass 'rainbow' livery. Here's my take of it on the 787, opting for the later version with the orange line under the windows and an enlarged wordmark.
Boeing 787-8 - N27901 / sn 0901
And here it is on the yet to be delivered Boeing 737-800 with the split scimitar winglet. I kept the engine cowlings and wingtips gray.
Boeing 737-800 - N37277 / sn 0277