Price units

Hi all,
is it possibile to show prices not per piece but per 100 Liters while the customer enters the quantity per liter.
Example:
Productprice is €60,- per 100 L
Quantity ordered by the Customer is 3000 L
Invoiced amount will be €1800,-

Is it also possible to display both prices incl and excl VAT?

Otherwise it would be helpful to code my own pricing module. Can someone give me any hint or example where to start?
What I am thinking of is entering some data like quantity, ZIP code and so on an then press a calculate button to get an individual price.

Thanks in advance
Bjoern

hi,
its not possible yet, but its been proposed:

http://nopcommerce.codeplex.com/WorkItem/View.aspx?WorkItemId=8057

go vote for it