According to the latest UNICEF report, the greatest humanitarian needs are: Food, clean water, hygeine, medical supplies and rebuliding of schools.
Humanists are helping by donating through SHARE (the Skeptics and Humanists Aid and Relief Effort), which will forward all donations on to Oxfam which has been active in Pakistan doing relief work for children and women prior to the floods.
The UN's report on the needs assessment for Pakistan is located here: http://www.unicefusa.org/assets/pdf/UNICEF-Immediate-Needs-Document-Pakistan-Flooding-26-August-2010.pdf
If you want to donate directly to the UN relief effort in Pakistan, you may do so here: http://www.unicefusa.org/work/emergencies/flood-relief/?gclid=CMmc_Inn36MCFYNR2godpj9GSA
The important thing is to help. These are our fellow human beings here. If we are to call ourselves Humanists, we must be willing to act on our compassion for others. Donate today!