What is the best FREE reader for Macintosh and for Windows?

[Geo (RIP)]

I'll try it. I love CDisplayEx but I'd like a good comic reader that I can recommend to my Mac friends.

Just check my post above for Mac viewers.
By the way I use a Mac laptop and a desktop model.

Geo

[John C]

I haven't used my Windows machine in a while (hardware problems), but the biggest surprise was that, somewhere along the line, my PDF reader of choice quietly added support for a whole bunch of formats.  And Sumatra PDF is also very lightweight.

http://blog.kowalczyk.info/software/sumatrapdf/free-pdf-reader.html

I don't read comics the same way I read books or magazines, so it's not quite perfect for me in this context, but it definitely does the job nicely.  And if you've already thought about getting rid of the Adobe monstrosity...

[baemr]

I use Comic Rack.  It is a great program!

http://comicrack.cyolito.com/

Not only can you view, but you can organize and convert comics as well.  You can also download webcomics.

[Poztron]

My viewing needs are pretty simple on my Mac. I bonded early on with FFView and have stuck with it. I also have Simple Comic loaded, but always go back to FFView. Were I to acquire an iPad, I might well explore other options...

And, as I can't say often enough at every juncture, my eternal thanks to the comic owners (especially JVJ) and scanners for this wonderful site. I've done my best to fill in some holes from my own limited collection, but I am way in debt to the powerhouse scanners out there. My motto: scan at 300dpi, at a minimum. I'm betting that resolution on monitors and pads will continue to climb in the future, to the point that scans at anything less than that will look unbelievably crude. But, I'm getting off-topic. Sorry! ;-)

[kusunoki]

I use Comic Rack.  It is a great program!

http://comicrack.cyolito.com/

Not only can you view, but you can organize and convert comics as well.  You can also download webcomics.

I love the idea of Comic Rack, especially with the itunes style interface on the database and the link up to Comic Vine, but the program runs super slow and uses up way too much of the computer's processing power. I've had to stop using the reader, which just freezes up completely whenever I try to use it, and enter my books in as paper. It's still worth it just a free organizer (mostly because of the [still quite flawed] Comic Vine connection), but it still runs slow even just doing that.

Did you do anything special to get it to run more smoothly on your computer? I would love to be able to use this at full functionality.

[baemr]

No, I didn't do anything special.  I have a pretty new computer, so that may be it.  Honestly, I mainly use it to organize and to download web comics.  It is great for that!  I do most of my actual reading on the iPad.  (I use Stanza for that)