The Ubercart Donation Products module allows the creation of donation products. These products by default are not shippable and allow an end user to specify an amount to donate before adding it to the cart. Once added to the cart the user can there also change the amount of the donation.
The Donate module, which is included, provides a page listing donation products either by group or individually. This supplied page also allows the user to set various amounts for differing donation products and add them to the cart all at once.
The ability to have a featured donation product is also available if the module Node Queue is installed. This featured donation product can be added to the donate page and/or as a pane during checkout. This pane only shows if no donations exist in the cart.