Speak is a command line utility for reading text aloud or writting the audio data to file.
Usage - speak [<Text>] -options
GlobalOption Description
Help (-?) Shows this help
ShowVoices (-voices) Show speaker voices available
Voice (-v) Set speaking voice
Rate (-r) Set speaking rate (-10 to 10) [Default='0']
Text (-t) Text to speak
UI (-U) Show progress bar
SaveFile (-s) Save to file
Speak was created with the intention that it should do one thing well and work well with others. In that vein, you can couple Speak with other applications. In PowerShell, there is a PowerShell applet that can retrieve the contents of the clipboard. Speak is designed to allow piping input.
e.g. Get-Clipboard | speak
Another option is to pair it with Watch. You can Watch a resource (Clipboard, Filesystem, HTTP, FTP) and trigger Speak.
e.g. watch Clipboard "speak" "{CLIPTEXT}"
You can also just use Speak on its own.
e.g. speak "hello world"