This page will mainly be of value to Australian residents, but people in other countries may also get some ideas for finding out about local disability benefits.
Theme parks (e.g. Wet'n'Wild, Movie World, etc) often offer a discount for a disabled child and their carer. As an example, general adult admission to Wet'n'Wild is $35.00 and the child rate is $22.00. The disabled child rate is $17.50, and one carer gets in for the pensioner price (I think roughly $22.00). It pays to ask!