HDR software for Mac

Are there any free HDR packages out there that are any good for OSX? Don't mind a Lightroom plugin if available.

You can do it in camera on the K-5 but only jpeg. Worth looking at to give you an idea if you like the effect. Not everyone's cup of tea but works well in places with little light like the inside of churches to allow you to get the light through the stained glass and the darker interior.

I've used it before but it was a while ago. I only shoot in RAW so must handle RAW files.

http://www.ohanaware.com/hdrtist/

it's quite a basic one but you could try it and see what you think - nothing lost. Actually reading on itdoesn't look like it reads penatx RAW's .

here's the blurb:

Technical Information

One HDR generation system.
4 Different tone mapping systems, compression,
Reads: JPEG, TIFF, GIF, PNG, BMP, PICT, SGI, JPEG-2000, Photoshop, PDF, ICO, TGA, ICNS, MacPaint, FlashPix, xBitmap, EXR, Radiance and various flavors of Nikon, Canon, Sony, Olympus & Panasonic RAW file formats.*
Write JPEG
Integrates with Funtastic Photos
System Requirements
10.5 (Leopard), 10.6 (Snow Leopard) or 10.7 (Lion)
Intel Processor
512mb of RAM (Memory)
20mb of Hard Disk space.
1024 x 768 or larger display.