ClipBoard Speaker is described as 'New entry is automatically added w/ text copied from apps.
New entry is automatically synthesized / spoken.
Keep playing entries in listing when Continuous Play is enabled.
Highlight spoken words while text is spoken, when option is enabled.
etc' and is a Text to Speech service. There are more than 25 alternatives to ClipBoard Speaker for a variety of platforms, including Windows, Mac, Web-based, Linux and iPad apps. The best ClipBoard Speaker alternative is Read Aloud Extension, which is both free and Open Source. Other great apps like ClipBoard Speaker are Balabolka, NaturalReader, eSpeak and TextAloud.