From the website:
This group was started to allow Heralds in the Society of Creative Anachronism (SCA) and other interested parties to be able to share graphics, in particular vector graphics, to be better able to help clients determine unique and suitable arms. Here Heralds from every Kingdom may join together to share and find charges and other images that they need not reinvent the eagle displayed. You will be asked to let us know who you are that we may keep out the "Big Luv" types but fear not, we shall welcome all. Pray come within, draw up a stool, and be welcome.