Sometimes I would like my project to start on measure -1 or even -2.  This is usually because I am working with a printed score and I need my measure numbers to match printed music that I am following.  I want to record pick up notes or catch an entrance that is just ahead of the first beat and not cut off the recording.  Or sometimes I want to use a recorded click that may be in eights or sixteenths as a count in.
 
Pro Tools spoiled me in this way and I've found that the feature is very handy.  Here's a video to demonstrate it.  https://www.youtube.com/watch?v=HkLzZ5W5Z-Y

you can't start before measure 1 but you can certainly have a count-in before playback or recording, check the metronome options.

negative measure numbers!!! yes!  even if it's only up to (down to) -2, I'd be happy. 
 
and make it SELECTABLE where you want your project to start and make it allow for insertion of measures before 1 if you start at 1 and decide later you want to add 3 measures before.

I would prefer the addition of a second timeline ruler, proposed here:
http://forum.cakewalk.com/m3097431.aspx#3098058
 

Yes, at least -1 for lead ins would be nice.

I have a similar request - probably similar enough that it would be implemented as part of the same set of options. Sometimes its been referred to as negative measures (I think Craig Anderton called it that in another thread), the need for me is the following:
The Scenario
When scoring to Video, I often have a start point for the music (SMPTE time code), but a run-up to allow the "live" musicians to sync up. I determine the tempo and meter for the first bar(s) and I need to I calculate the SMPTE time offset for the start of the run-up bars. If I get the tempo wrong  (or I'm sloshing about to figure the right tempo), I need to recalculate the pre-run start point every time I change that initial tempo. If I had the negative bars, I could set the SMPTE time at 1:1 and then the run-up would be calculated for me.
 
Tempo variability
While the run-up is most often at the same tempo as the real bar 1, bar -2, -1, 0 sometimes have tempo changes built in - this can happen for a number of reasons, but often to give the live musicians the ability to accel or rit immediately in bar one in a musical way. The analogy for this I like the best that jumping into a moving car is difficult to do, and it's even more difficult if the driver can't keep a steady pace.
 
It's also important to be able to run-up the video from an appropriate point, and that may require more than two measures.
 
Why not use count-off?
The problem with using Countoff is twofold:
1. If the player anticipates (plays on top of) the first beat, it's cut off.
2. It's a steady tempo - not accel or rit.
 
Hopefully this will make it in someday.
 
PS - Sorry Noel - I know we talked about this years ago, but I couldn't clearly articulate the process I explained above. Hopefully it is clearer here.

I haven't updated my license this year but I don't think this one has been considered.

I'm current Dave, and there are no negative measures yet.

Thanks for the update.  Back to our regularly scheduled program.  

I have hoped for this feature for years.
 
Edited to add: This comes in especially handy when you're reading from a written score. Say you're looking at measure 256 in the score and want to cross-check that same place out on your recording- Did I play the triplet smoothly there? Did I get the right feel?
 
If the same measure in the score could actually always be found at the identical measure number (in this case,256) in the Sonar recording, too, what a treat! No extra steps.
 
Of course it isn't hard to remember or look up how many measures you left blank and/or containing introductory material before the measure marked as "1" in the score at the beginning of your recording of that particular piece. Then you only need to add that number to the measure number in the score (256) to figure out what measure you should go to in the recording, but wouldn't it be great not to have to?
 
So simple, straightforward and clean!  One less little frustration. One tiny obstacle less between you and the music.