P.S. By the way, my current ideas are 薯仔薯女 or 憨男憨女 because I need to include the two sexes. But I don’t like both as they are not close enough to the essence of the English meanings.
24 July Update:
Thanks to Horace’s suggestions: nerd = 書蟲, geek = 電腦怪, geeky = 搞機
Thanks to my friend Ms. Y’s suggestions:
nerds – 宅男/女(御宅族)、xx迷(eg.電腦迷)、xx蟲(eg.蛀書蟲)、“kai”子、隱閉青年
geeks – 奇才、發燒友、怪胎、騎呢怪、怪人；“mook”嘴、茂里
geeky – 怪雞、怪誕、無厘頭、異相、騎呢；碌葛、蠢、鈍、“削“
While these are all good suggestions in some ways, they don’t quite fit the context I am dealing with, which is a collection of movie/TV stars (see this comment here).