Disclaimer: As some of you know, I use have been using ACDSee Pro for my image cataloging and processing, and occasionally recommend that product here. I'm not affiliated with the company, although I am a moderator on their forum.
ACD has released a "beta" version of ACDSee Pro 3. It's a free download, but hopefully you understand what "beta" means: it's still under development, may not have all the kinks worked out yet, and the beta will expire when the final product is released, at which point you'd have to buy it to use it. The idea is to get people using it and giving feedback on it to make the final product as good as it can be.
With this release, ACDSee is moving toward something more Lightroom-like in overall look and feel, although it maintains one big advantage it has always had over LR: the fact that you don't need to explicitly "import" photos into its system in order to browse or work with them. But Pro 3 adds one very important LR feature that ACDSee had always lacked - it can now do all the same sort of "non-destructive" processing on JPEG files that it had previously offered only for RAW. And it adds several new tools to that non-destructive facility, including an "advanced color" tool that lets you control all sorts of attribute of color (not just simple WB and saturation sliders), plus some lens distortion / perspective correction tools, and an improved version of the already way-cool "light eq" facility that performed a sort of local contrast enhancement to increase the apparent dynamic range of a picture.
I think this release may of particular interest to fellow Pentax users, because it is the first version of ACDSee Pro that can browse PEF files by displaying the camera-embedded preview rather than generating its own preview on the fly. As a result, it's *MUCH* faster for browsing. Of course, if you do any processing on your RAW files, it will display your processed version instead of the embedded version.
There are of course other changes too, but overall, I think the most significant are the improved non-destructive editing capabilities (new tools & ability to process JPEG this way) and the fast preview of RAW files. I've actually been using it for a few week now (under non-disclosure until yesterday), and even though it is "beta", it's actually surprisingly robust.
Here's the link:
ACDSee Photo Software