menu items widget

Hi,

i would like to have a plugin or widget that displays sub menu item when a particular page is displayed.

for example, if i have the following menu:
home | services | contact us
service 1
service 2

if i click on services, services page should be displayed with a small sub menu displayed on the right side showing only 2 items: service 1 and service 2.

does something like that exist ?
thx