Consumer applications of such technology could range from finding studs in walls to authentication of important documents. Businesses could use it to detect counterfeit money.
Manufacturing companies could apply it to process control.
There are also more communication channels available in terahertz than the range currently used for wireless communication, so information could be more rapidly shared at this frequency.
Terahertz can also be used for imaging to detect cancer tumors, diagnosing disease through breath analysis, and monitoring air toxicity.