Links to learn more about Islam:

Islam101 A very good introductory website

Quran Explorer A Quran browser with different translations and audio recitations

MP3Quran Get Quran recitations for different reciters in MP3 format

Tafsir Quran commentary by the classical scholar Ibn Kathir 

Recite A flash recitation player with different reciters

SearchQuran A Quranic search engine

University of Southern California Muslims Texts Compilation

40Nawawi Hadiths The 40 Nawawi Hadiths in 13 languages

AlMuhaddithProject A Hadith search engine 

Introduction To The Science of Hadith