Save the environment .. ;-)

This one gave me headaches:

TEST >unset abc

TEST >echo dummy text | set abc=something

TEST >set abc
TCC: Not in environment "abc*"
Problem is the "|" makes the next command to start a new instance of tcc
Any set variable will be lost when this instance exits.

What would be a good way to "save" abc?
(beside writing "abc=something" to a file and reading it afterwards)