RogerH
Tried rewire today. Is it possible to send MIDI from reaper to Sonar via Rewire?

No. Sonar can be a ReWire host, but not a client. MIDI can flow only from host to client. 

TomHelvey
Now I want to get a copy of Reason to play with :)

You can download Reason. In demo mode it does everything except while you can save documents, you can't open them. 
 
Reason Essentials is less expensive, but doesn't offer anything significant that Sonar doesn't already have.

Another ReWire for Reason user here.

Anderton

Mosvalve
Rewire is greyed out in Sonar. 
 
Craig, I am running Sonar 64bit. I found rewire.dll in c:\program files(86)\common files\Propellerheadsoftware\rewire. This file version is 1.8.1.40960 dated 2-17-14 and I assume this is a 32bit version. In c:\program files\common files\Propellerheadsoftware\rewire is empty but there is another folder called Rex with a Rex Shared Library.dll file in it. The link you provided contains version 1.7 and tells me when I run the installer that I already have a newer version of the file. I cannot find a 64bit version of the rewire.dll on Propellerhead website. Studio One finds Waves and Melodyne rewire when it loads and like I mentioned I used to see Waves rewire in Sonar. I'm stumped at this point. I think the 64bit version gets installed by Reason. I'm assuming when I installed X3 64bit that the 64bit rewire would be installed to but apparently not. Any help is appreciated. I would really like to try rewire.

On my computer a 64-bit version is in C:\Program Files\Common Files\Propellerhead Software\ReWire\ReWire.dll. I'm going to guess that's where Sonar looks for it, because you don't have it and Sonar can't ReWire.
 
I can't find a download either, so at this point I'm grasping at straws and maybe someone else will have an idea of what to do...I think maybe the 64-bit version should have been installed with Sonar. Perhaps doing a minimal Sonar re-install will give you the 64-bit dll.

Or, try this: I searched on ReWire.dll and eventually, found a bunch of ReWire.dll files sprinkled all over my computer...in the Live 9 Suite Redist folder, C:\Windows\SysWOW64, C:\Program Files\Common Files\Propellerhead Software\ReWire, ProgramFiles\Waves\ReWire, Samplitude, Sony Acid, etc. If one of these is the 64-bit 1.8.4 version, try copying it into C:\Program Files\Common Files\Propellerhead Software\ReWire, re-boot, and maybe Sonar will see it.

I found a 64bit version in my Waves folder and copied it and now rewire is no longer greyed out. Two things show up under rewire. Melodyne and Waves rewire. Now hopefully I can understand the tutorial you provided and learn how to use it. thanks for the help.

I have Komplete and ST3 plus a few soft synths and piano vst. After playing with the Reason Demo, I felt that  ST3 samples are way better than NNXT.  Ok , it s not fair to compare 30Gigs to 3 Gig.  Not sure if Reason 8 would bring anything very different to the table?
 
However, I also have Miroslav and Kirk Hunter Diamond Orchestra. Does anyone know if think these VST can work within notion 5 for some orchestration. Or via Rewire to Sonar. Any opinion?

Did it ever work properly?

musichoo
I have Komplete and ST3 plus a few soft synths and piano vst. After playing with the Reason Demo, I felt that  ST3 samples are way better than NNXT.  Ok , it s not fair to compare 30Gigs to 3 Gig.  Not sure if Reason 8 would bring anything very different to the table?

IMHO Reason's standouts are the Thor and Malstrom synths, Kong drum module, Vocoder, OctoRex REX File player, Subtractor if you use the Combinator function to stack them, and of course, the ability to patch anything to anything.
 
What I like about the NN-XT isn't so much the samples that come with it, but the ease of creating your own sampled instruments.

I end up buying notion5 after noticing a few guys in this forum using it. I owned a 2003 version of Finale that could only work with win2000 and was left hanging dry when my computers go win 7. I was entitled to cross grade to notion 5 for about 64 bucks. That's half the price to upgrade to finale 2014. Thanks Mr Anderton for mentioning this to me. I will be trying to rewire notion to sonar soon.

musichoo
I will be trying to rewire notion to sonar soon.

Please let us know how it works for you. I think this is something that would be of interest to quite a few people on the forum.

Craig, I read your article and it is excellent, as always.  Today, I don't think I need Rewire, but you never know what tomorrow will bring so this is great information.  Thanks.