With dbcontext you can:
transform a DocBook XML/SGML book or article to pure ConTeXt, or directly to DVI, PostScript, or PDF,
compile separately the produced ConTeXt file with texexec, to produce DVI, PostScript and PDF files,
have a real UTF-8 support,
convert on the fly the figures included in the document,
create an index,
write ConTeXt mathematical equations,
write MathML equations,
write complex tables,
use callouts on program listings, screens, or images,
have revision bars,
customize the output rendering with XSL configuration file or XSL parameters (not complete),
customize the output rendering with your own ConTeXt layout.