On Thu, 3 Jun 2010, Marco wrote:

> On Thu, 3 Jun 2010 17:02:24 +0200, Peter Münster <pmlists@free.fr>
> wrote:
>
>> [...]
>> Perhaps your pdf-viewer does not support javascript.
>> I use acroread version 9.3.2 
>> 
>> Cheers, Peter
> After short research I found out that most pdf readers don't support Java
> Script (so do xpdf and sumatra). So, this is not really a portable solution.
>
> Any hints for achieving the same result in a portable way without Java
> Script appreciated.

I think that a luatex solution should be easy (for Hans, hint hint).

Collect everything on a page, and do some attribute magic to reveal it one 
by one (or change colors, etc). Personally, I occasionally use a primitive 
and ugly solution

\StartSteps{4}
\startitemize
  \item ...
  \2{\item ...}
  \3{\item ...}
  \4{\item ...}
\stopitemize
\StopSteps

where \StartSteps collects its body, typesets it 4 times. In the first 
iteration, \1 = \donoting, everything else is \gobbleoneargument; in the 
2nd iteration, \1 and \2 = \donothing and so on.

Aditya