Good question, here are mine:
For Greek & Hebrew translations:
http://www.blueletterbible.org/For General Bible searching:
http://www.biblegateway.com/New American Bible:
http://www.nccbuscc.org/nab/bible/index.htmCatholic Encyclopedia, etc.:
http://www.newadvent.org/Catechism of the Catholic Church:
http://www.scborromeo.org/ccc.htmEWTN Library:
http://www.ewtn.com/vlibrary/search.aspApologetics Without Apology:
http://www.catholicapologetics.org/aptoc.htmTouchstone Blog & Mag achive:
http://merecomments.typepad.com/First Things Blog & Mag Archive:
http://www.firstthings.com/blogs/firstthoughts/Well that's nine...the other sources are too diffuse to pick a 10th.