I use this projector for video and image files. In my opinion, it is best suited for impromptu displays for groups of 5 people or less. I always load all my materials on a 16GB class 6 Micro SD card which I leave plugged into the projector. I seldom use it connected to my linux gear, tho it works fine with all my 'nix machines including my Nokia N900. It's great for quickly displaying something on a white board in someone's cubicle. You don't need a lot of complicated equipment and a laptop because everything is thoughtfully self-contained.
Although software does come with the projector for converting PowerPoint presentations to a portable format that can be loaded to an SD card (as well as converting videos), I don't use that software because it's for windows and I'm not a windows user.
The PK301 is larger than my 3M Pro120 with greater resolution and a significantly brighter/sharper picture. I don't notice any of the rainbow effects that are sometimes a nuisance on my 120. It throws a 32 inch diagonal 16x9 aspect picture from 4ft away which is bright enough to be enjoyed in most office lighting conditions (overhead florescent). Usually, I'm just holding the projector at belly button height. The focus-ring is great and makes it easy to get a tack-sharp picture. You can operate all the controls with your thumbs because they are centered on the top of the machine with the exception of the on/off button which is on the side. It accepts a camera tripod (not included), and I bought a mini-one to set on a desk/table top for when I connect to my netbook or something.
Battery life is much, much less than the 3M (I get about 30-40 mins), but unlike many projectors, you can use the power cord while the projector is running for unlimited working time.
I use Mpeg 4 video formats with this projector when playing programs from the Micro SD card. I experimented with several tweaks and bit rates and discovered that the internal video player software cannot play variable bit-rate MP4 encodings. It does, however, play constant bit rate, quality, or quantization videos very well. I settled on MP4, Level 5, 720x408p (yes, 408 - remember it's 16x9), 29.97fps, constant quality 13, with 128kbps AAC 48khz audio. You need a class 4 or above SD card because the video will stutter if played from a class 2.
While you're playing a video, the < and > buttons allow for RR and FF, and the up and down buttons control the volume. The remote (sold separately here at Amazon) has an additional volume control on it as well as a mute button. You can shut off the projector from the remote, but you cannot turn it on. And order yourself a CR2025 lithium battery for the remote (it doesn't come with a battery). I got mine at Target, but they can be hard to find.
And at the end of the day I set the projector on the hotel nightstand and flip the tripod head to vertical. Then I can lie in bed and watch a movie or music videos on a 50" video picture projected on the ceiling (which is almost always white in hotels). I can shut off the projector and there's no lingering cooling fan to keep me awake.
--- UPDATE
The internal media player cannot play Video files > 2,048MB. If a movie exceeds that, the directory shows a negative size (meaning the code doesn't use long integers) and you'll get an error message about an unrecognized format. You must break the movie into smaller files or reduce your encoding quality to constrain the movie to 2GB.
--- UPDATE
This projector finally failed. It was a rather slow death. The image started to display a few dead pixels. They eventually spread until the picture was unusable. It did this over a period of three days, which was good because it gave me a chance to make other arrangements rather than just quiting in the middle of a presentation.