persistant psql feature suggestion

Greets,

Just a thought for a psql enhancement, afiak, it is not easily possible for persistent connections to a database in a shell script..
The ability for psql to remain in the background reading from stdin and writing to stdout until explicitly killed. More specifically, so a shell scriptor can have "persistent" connections to the database by calling psql once(leaving it in the bg), and redirecting stdio through a fifo(mkfifo)(sending queries by echo > fifo, and fetching results by cat fifo).
When I have tried this in the past it will read the query, execute it, and exit when the results are cat'd from the fifo.

Just wanted to make sure nothing similar enough was already in existence, and if anyone could easily implement this. If no one wants to, I suppose I'll look into doing it if it's worth doing. :)

Cheers,

James