Lis Riba points us to a wonderful site to help keep track of our omer counting. We (Jews) count each night between the Festival of Matzah, Pesach, and the Festival of Weeks, Shavuot (See Leviticus 23:15). The hebrew word for the sheaf mentioned in this counting is omer, or with the definite article ha'omer hence the play on words. I should note, though, that the Homer calender may be wrong with respect to the dates of Yom Ha'zikaron (Day of Rememberance) and Yom Ha'atzmaut (Independence Day). The Town Crier informs us that Israel has pushed those holidays back one day.
UPDATE: I should point out that pushing those holidays back a day just applies to years on which Yom Hazikaron would otherwise have fallen on the first day of the week (Saturday Night/Sunday). Likewise in years on which Yom Ha'atzmaut would have fallen on Friday or Shabbat those holidays get moved earlier by a day or two days respectively. The general rule has not changed, only one additional exception has been added.