Here is a step-by-step process on how to achieve reverse reverb on a vocal track in Logic Pro 9:
I. Record a vocal line (The example used was my rather boring spoken voice recorded about 8″ from a Samson C01 condenser)
II. Bounce down this version and rename it so that when you reverse the audio, the original file remains the same.
III. Add the file back in to the session from the Media sidebar

IV. Double click the region to bring up the Sampler Editor window and from the drop down menu select Functions > Reverse
V. Add your chosen reverb to the reversed track
VI. Bounce down this version ensuring you capture all the reverb

VII. Now import the reversed reverb track and reverse it again to bring it back to its original playback
VIII. Line up the takes and blend them together.
Extra
One final point for lovers of horror films and creepy voices; you can add in more vocal tracks with their pitches shifted to achieve that demonic/possessed sounding voice.
In this example I added four extra tracks to the original reverse reverb mix. For the first two I used a vocal transformer to bring down the pitch to create a very deep voice and for the other two I used a pitch shifter to raise the pitches greatly, but in dissonance with each other. When panned and set back in the mix with some EQ the effect becomes a little more subtle and a lot more creepy – especially if you replace my neutral dialogue with “I want to eat your face”.
I hope you found this useful and please leave any questions or comments down below 🙂
Neil