Swivel viewers are fundamentally simple, but tricky to communicate to end user what they can do. Google added a feature to Picasa Web Albums that "lets you flip through photos in an album in "Full Screen" or "Slideshow" mode by dragging left & right on current photo. This works well if you put an object on a turntable, and for other albums like embedded album viewer. So any albums you've embedded already support swiveling.
If you prefer to host a viewer and images on your own site, check out Swivel Viewer site, where you'll find open source embeddable album viewer that also supports zooming & panning. Alternatively, you can go directly to page about hosting own viewer, or check out these other albums from gallery. Also, see tips on how to take your own 360 views, and even some sketches for experimental high-volume object scanner.