(from JewishGen.org) - It can convert a civil (Gregorian calendar) date into the equivalent date on the Hebrew calendar, and vice versa. It can also display Yahrzeit dates for consecutive years.
Hebcal Interactive Jewish Calendar
Generates a list of Jewish holidays and candle lighting times customized to your zip code, city, or latitude/longitude.
Bookmark this page for weekly Shabbat candle lighting times.
Yahrzeit, Birthday, and Anniversary Calendar
Generates a list of Yahrzeit (memorial) and Yizkor dates, or Birthdays and Anniversaries.
Hebrew Date Converter
Convert between Hebrew and Gregorian dates.
Aliyah-by-aliyah breakdown for weekly parshiyot - Triennial cycle.