Check out this mellotron plug in
I agree. I know it, and I use it frequently. It’s great for those particular situations where it needs to be more realistic than a string machine like the Solina (for which I use the CheezeMachine VSTi plugin), and less realistic than multisampled strings (for which I use either the Pop Strings patch in the Sampletank Free edition, some cool orchestral soundfont with sfz, or the really good string patches I found for the free DS-404 VSTi sampler). This is the ‘classic’ mellotron sound of Procol Harum, Moody Blues, Tangerine Dream and The Beatles. I do miss a flute patch, though…
OOOHhhh! WAAYY COOl!