Maiden's prayer

half - pregnant
answer to a maiden's prayer

Meanings at least.

Half-pregnant. An impossible state to be in, because (obviously) it's a black or white deal, all or nothing. Often used to refer to someone who's trying to sit on the fence when it's impossible to do so - "you can't be half-pregnant, you know."

There is also the similar sounding "partially pregnant" which refers to the process of getting someone hooked on something: e.g. giving away a useful piece of software for free then, when people find it indispensible, insist they start paying for it. I first heard the term from an ex-IBMer.

"Maiden's prayer" - excuse me, but that was the daughter of Bill Clinton of "I like to splash out on my girlfriends" fame? A "maiden"? Not wishing to slur an unknown woman, one senses that a degree of artistic-licence may perhaps be being applied - unless the act of being on one's knees "praying" is more subtle than I gave credit for!

"The answer to a maiden's prayer" is often used tongue in cheek (just never mind the possible associations here), but when used straight, it means the perfect man, Mr. Right. Roughly equivalent to "tall, dark, and handsome"--although in reality many women give greater priority to being employed, being willing to converse, and having some hair.