Prochain RER is a Widgets software developed by Etienne M.. After our trial and test, the software is proved to be official, secure and free. Here is the official description for Prochain RER:

Edit By BS Editor: Un Widget très parisien !
Donne la liste DES prochains RER à un arrêt donné.
Très pratique pour, par exemple, Quitter le boulot "juste à temps" !
Fonctionne pour les RER A, RER B et Transiliens (RER E et Banlieue). Utilise les informations temps réel des sites www.ratp.fr et www.transilien.com.
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Gives the next RERs (Suburban Trains in Paris) for a station that you choose. Very useful, for example, to know when to leave for work and get there "Just In Time!" Works with RER A, RER B and …Transiliens. It fetches the real time information from the websites www.ratp.fr and www.transilien.com.