Saw a Youtube video regarding fattening up vocals by detuning clones sharp/flat by 3,6,9,12 hundredths panned hard left/right and that seemed (to me) to work very well.  What Sonar-compatible VST will do this?  Not the transpose function.  Can't find any docs for the Cakewalk Pitch Shifter, so don't know what those sliders are referring to (I.e., no units).  ???

How about using Melodyne or V-Vocal?
 

• Clone vocal track 6 times and apply +3, -3, +6, -6, +9, -9, +12 and -12 detuning manually (select whole clip, then drag tuning up/down by mouse).
• Bounce clips.
• Add EQ high shelf to boost treble.
• Pan +3 left, -3 right, -6 left, +6 right, +9 left, -9 right, -12 left, +12 right
• Create New Aux track. 
• Set cloned vocal tracks outputs to the new Aux track. 
• Add some compression and finetuning EQ to the Aux track.
• Set Aux track output to Vocal bus.
• Create track folder.
• Move all the new tracks to the folder.
• Now you can mute and solo vocal fattening tracks by Track Folder mute and solo buttons.

 

Panup you rock.  Thanks much for the trouble putting that step-by-step together.  I'm printing it out for future employment.  Thanks.

Another option is to use the Loop Construction View to do varispeed-type techniques, then DSP time-stretching to restore the desired length. Week 20 of Friday's Tip of the Week tells how to do fine-tuning with the LCV. Since fine-tuning using this method will change the length, ctrl+click on the clip end and drag to edit the length.
 
You also might find the Week 44 tip useful, because it describes using Take Lanes to get huge massed vocal sounds.

If you're looking for an easy way to do this automatically then the Waves Doubler is good.

If you have full Melodyne, you may also want to tweak formants up/down to get more difference to the doubled tracks.
 
As sharke mentioned, Waves Doubler is great plugin to do this automatically. 

1/100th of a semitone is a "cent". So you know on guitar tuners and pitch tools that have a "cents" readout/adjustment? That's what those numbers/increments represent.
 
Any pitch shifter that allows adjustments in cents will work. IIRC the DSP Transpose function allows for adjustments in cents but yeah, Melodyne should be able to as well and perhaps the Loop Constructor in the Pitch options (I don't recall if it adjusts by cents).
 
I have not thoroughly messed with those tools though so I may be wrong about one or all but you are definitely looking for an "adjust pitch by cents" parameter.
 
https://en.wikipedia.org/wiki/Cent_%28music%29
 
Cheers.

If "blindly" shifting pitch on an entire track to that fine degree of resolution, Audacity would be another solution that is free (for anyone reading without Melodyne). The transpose algorithm in SONAR is limited to whole number semitones, but should be revisited as the desire to detune audio by slight amounts it fairly common (i.e., the "432Hz crowd").

I downloaded the demo of Waves Doubler, intending to purchase while still on sale.  But then I said to myself, "Self, why don't you experiment before forking out more money during Christmas?"  So I did the following (building on Panup's procedure) and frankly I can't tell the difference between the Waves Doubler and this approach.  Can you?
 

1. If necessary, Melodyne or Autotune vocal track.
2. Clone dry vocal track and rename “VocFat”. Add Cakewalk Pitchshifter. Adjust delay time of Pitchshifter to 15ms, and route output to new Aux track “FatAux”
3. Pan hard left, and Clone 4 times using “Repititions” option.  On last clone, Pan hard right, adjust delay time to 10 ms,  and clone 3 more times.  You now have 8 clones routed to Aux track “Fat”, left delayed 15ms and right 10ms.
4. Pitchshift left clones +3, +6, +9, +12 and right clones negative. 
5. Add compression and EQ high shelf to boost treble to the Fat Aux track.
6. Move Fat Aux to top of VocFat tracks and set Aux track output to Vocal bus.
7. Create track folder. Select all fattening tracks, right click and “move to folder”.  
8. Use FatAux fader to adjust amount.

a couple or five of things ---
 
1) if there is anything but a solo line, then you need to consider the other voices
2) 'detune' by a cent will probably not be heard
3) the best 'detunes' are those that take into account the harmony --- if your target melody is on a note that is the third of a major triad, go for detune down significantly --
4) if your target melody is on a note that is the fifth of a major triad, detune up a very small amount ---
5) if you are on a minor chord and your target melody is on the third detune up significantly.
 
 Greg, not to be unkind, but that procedure is wonky wacky and woeful.