I currently use eSpeak.exe to be able to do (basically):
espeak "This is an arbitrary sentence."
It speaks out the string, but all the supported voices (as far as I can tell) all sound like cold, dead robots, giving me a creepy, post-apocalyptic feeling rather than the warm "AI secretary" I desire. It makes me unwilling to use this for much, since it sends me a cold shiver down my spine every time.
Is there really no "modern" such "voice program" which works on the command line, doesn't cost money and sounds like a human female instead of a soulless machine? I have heard very naturally-sounding robot voices for many years now, but I suspect that they cost $59,998/month and are only available for enterprise customers who spend at least 4 million per quarter and have a minimum of 5,000 employees... I'm just a lonely guy with a cheap PC and empty wallet.