I'm a mac guy. I use Metric Halo hardware and their software for record capture (I do mostly location recording). It's rock solid and the ULN-8 preamps and converters are among the best out there. It also has great DSP with 80 bit summing, so there's essentially a digital mixing console built into the hardware that can mix 18 channels per box from my DAW plus 16 external channels per box. The DSP includes really good good EQ, compression, reverb and a transient controller. To my mind they are the Alembic of interfaces. Their customer service is also great. I once had an issue an hour before a gig in Colorado and emailed the company. I got an email back with the solution within a half hour from the president of the company at 9pm on a Saturday night, his time. You won't get that from MOTU, Avid, Apogee or any other company.
For mixing and editing I go between Pro Tools (now that it's free from the Avid/digi hardware requirement shackles) which I think is the most intuitive design for someone like me who came up editing with a razor blade, and Logic, which is reasonably good. I also use Digital Performer at times, especially as a live mixer when using multiple boxes as it will do its own aggregation with low latency (I use it in my in ear rig for my drummer, who controls it with an Alphaport while I make my mix in the Metric Halo Console.).
For Windows, I'm not sure what to offer. I've heard great things about Nuendo, Sequoia and others.
Reaper does seem like an intriguing solution. I tried it but found it less than intuitive for my workstyle and I don't think it's worth my time to learn yet another paradigm, but I don't hesitate to suggest that everyone check it out. I think their method of development and community involvement is very cool!