Token support for input formats

Have you thought about using tokens that could be inserted into a regular text? I have recently used your module API for such a purpose and needed to enter all the variables using PHP which is rather uncomfortable. I have seem a similar approach; using tokens to insert content into a textarea field.

It could be formed this way perhaps: [currency:from,to,value] and that could spit out the amount of money in the desired currency if supported.

If this has not crossed your mind, I could possibly look into it when there's more time.