Yap is on the workbench and I can promise that support for PostScript will be improved significantly. The motto is: Every DVI document that can be viewed with a PostScript viewer (after DVI-to-PostScript) can be viewed with Yap.
Take this PSTricks sample:
\documentclass{article}\usepackage{pstricks}\usepackage{pst-char}\usepackage{pst-slpe}\usepackage{pst-blur}\usepackage{graphicx}\pagestyle{empty}\parindent=0pt\begin{document}\DeclareFixedFont{\RM}{T1}{ptm}{b}{n}{4cm}\DeclareFixedFont{\Rm}{T1}{ptm}{m}{n}{2mm}\psset{shadow=true,blur=true,shadowsize=10pt,% blurradius=5pt,fillstyle=slopes}\rotateleft{\pscharpath{\RM MiK\@T\kern-.1667em\lower.5ex\hbox{E}\kern-.125emX}}\end{document}
Yap 2.5 will render the sample as follows:
(By the way, Yap 2.4 will show you this:

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