Off the top of my head:
Benjamin -- son of my right hand
Benedict /
Benedicta -- blessing
Mercedes -- mercy
Mirabel -- miracle
Clement /
Clementine /
Clemence -- merciful, mild
Callisto /
Callista -- the most beautiful
Aislinn /
Aisling -- dream
Angharad -- much loved
Ambrose -- immortal
Fidel /
Fidelia -- faithful
Tadhg -- poet
Casimir -- he commands peace
Consuelo -- consolation
Constanza -- constant
Hilary -- happy
Esperanza -- hope
Alma -- soul
Rene /
Renee /
Renata -- reborn
Praskovia /
Praskovya -- preparation
Frederick /
Frederica -- peaceful ruler
Ghislaine /
Gisele /
Giselle -- pledge
Placida -- peaceful
I'm sure I've forgotten some great meanings. I can't wait to see what others have come up with.