A emacs lisp command that uses pdflatex to compile a pdf version of the active buffer, then view it with evince.

view-latex.el

(defun view-latex ()
  (interactive)
  (if (buffer-modified-p) (save-buffer))
  (shell-command (concat "pdflatex " buffer-file-name " >> /dev/null"))
  (shell-command (concat "evince " (substring buffer-file-name 0 
					      (- (length buffer-file-name) 4)) ".pdf >> /dev/null")))
;Obviously, replace "pdflatex" and "evince" with your own latex and pdf viewer systems, respectively.
;