I've done some searching to find links relevant to issues and ideas mentioned in the Haggadah. They appear woven throughout the text of the online Haggadah. Where appropriate, the button links to the page of the Haggadah, otherwise the button links out. The number in brackets is the date [yymmdd] the item was added.
Much more exists than what I have here; I made an editorial decision about what I found interesting, unique, special and would serve as door-openers to further exploration.
This is a subject organized list of them. It exists as much for me to be able to check currently active links as it does for others to be able to use the Haggadah.
Lights In Action Passover links
Chabad's Haggadah collection/bibliography
Haggadah for the Liberated Lamb
The Howard Rheingold Family Haggadah
Temple Emanuel's Virtual Seder
Rabbi Amy Scheinerman's Haggadah pages
Child-centered Passover Haggadot/stories of John Kador
Lights In Action four Questions
Four Questions of Meloncholy : Poems by Tomaz Salamun
Four Questions the Kidlink Response
Lutheran guidelines for the use of the Passover Haggadah
Wine (see internally for multiple links)
Bioethics and the Passover Lamb
Mahomet-Seymour Junior High School Holocaust Project
Mutual Aid and Self-Help Groups [970404]
Congress of Secular Jewish Organizations
Jewish Reconstructionist Foundation
Mazon: A Jewish Response to Hunger
Union of American Hebrew Congregations
Last modified on 24 January, 2001