The Epson Powerlite S4 recently replaced their S3. For years, Epson's entry level projector entries, have been the top, or close to the top, selling entry level projector. This is not likely to change anytime soon, with the introduction of the S4, a low cost LCD based projector that is a low resolution projector (SVGA). There are far, far more XGA projectors out there, but the nature of "entry level" is that the Epson and other entry level SVGA models, have impressive sales numbers. I'll discuss issues of choosing SVGA projectors over XGA models (to save a few bucks) elsewhere in this review and also in our Seven projector comparison review that includes the S4.
The EpsonS4 image shown above, is of the front of the projector, with the sliding door protecting the lens, in the closed position.
Tthe Epson is a $699 list price projector, although dealer prices will vary slightly, don't expect a large discount off of that price. You are not likely to find any competitors for significantly less money, unless it is a discontinued model, or a refurbished projector. The S4, like it's predecessor should be extremely popular with the K-12 education crowd, as well as for thrifty businesses on a really tight budget.