UAD SSL - Use it all the time and haven;t found a better sounding final mix compressor and I have many including others by UAD, Waves and of course Cakewalk.  It does the job without coloring the sound too much and is as transparent as you want it to be while still pulling the mix together.  Also, I use the UAD Ampex 102 along with it which really works great!

no iLok for Fabfilter Pro-L and free trial available

Over the years I've tried to be disciplined about maintaining levels such that a limiter set at -0.1 would be redundant.  I quite like the idea of setting a limiter this way, but more and more I am trying to manage the gain staging across the signal path from track to bus (to bus...) to the master out so that the levels are somewhat consistent across projects as well as within them.

Usually I have either Ozone 5 or the Concrete Limiter or Waves L1 or even Boost 11 on the master bus, but I have these set to disabled while mixing.  At some point I'll enable these just to get a sense of their effect, either in terms of assessing various loudness possibilities or as an experiment for the learning/fun of it.  

The cool thing about running your own studio for your purposes is doing things that match your workflow, regardless of whether they would be acceptable by the public at large.  I think the closer you get towards mastering, the more the accepted ways might be the preferred or arguably "better" ways, and in that case I'd lean towards what are accepted practices in the professional world of mastering.  Sitting in on such a mastering session, as someone suggested, is a great exercise and learning experience.

I don't think you could go wrong with T-racks or Ozone 5. Both are very good. Fab Filter is very pretty! and it sounds great. Limiter No.6 is the best free limiter I've found.

the boost 11 that ships with Sonar I think is great.
does what is says and no more (no 'side effects' you dont want like with some other limiters).