After a couple of years of development, the first alpha release of Haiku had come out.
The idea behind Haiku, which is in itself a BeOS clone, is to have a simple, sleek OS that doesn’t bundle the layers upon layers of crap that most of the many OSes of today have.

This is the splash screen.

The CD-ROM can be used as either a live CD or as an installer.

This is the default Haiku desktop.
For being an alpha release, Haiku seems pretty stable and just about complete.
The Deskbar/Tracker was actually released as open-source by Be before they went under, and this is what Haiku uses, so the Haiku desktop feels just like the old BeOS desktop did.
On the negative side, however, sound and printing both do not work yet.

The Deskbar in the upper-right corner provides a menu of programs and options, as well as a list of open applications.

The Tracker allows you to quickly browse files, with a minimal impact on system resources. Files can be viewed as big or small icons, as well as in a details view. You can copy/move files through drag and drop like the popular operating systems.
The desktop is also a folder, and files, folders and links can be placed on it.

Haiku can mount ATA, SATA, and CD-ROMs.
Supposedly it can mount USB devices but I could not mount any of the drives I tested it with.
Interestingly there is no option to mount floppy disks, even though BeOS had this option.