Lectura recomendada: George Orwell - 1984.epub


A Billion Digits of Pi


Computational knowledge engine: http://www.wolframalpha.com/


Free Internet Chess Server
Here you can play chess over the internet for free.
Jugar online: http://www.freechess.org/Login/jin/applet.php

Lichess.org

The purpose of Lichess is to provide a simple chess game interface. It requires no registration; you don't need to create an account to play.

MacMillan Dictionary
Diccionario online de inglés donde puedes ver la definición y escuchar la pronunciación.

TED: Ideas worth spreading

TED is a nonprofit devoted to Ideas Worth Spreading. It started out (in 1984) as a conference bringing together people from three worlds: Technology, Entertainment, Design.

http://www.manythings.org/
This web site is for people studying English as a Second Language (ESL) or English as a Foreign Language (EFL). There are quizzes, word games, word puzzles and proverbs.

Ajedrez (frases celebres).pdf

Temas tácticos en Ajedrez.pdf