Millennium Declaration
The purpose of this section is to provide convenient links to the UN organizations listed on the UN System Chart.  It doesn't exactly match the format because the UN page was too wide, but the headings and the content below the headings do correspond to the org chart.  I've listed organizations with major functions and websites first.
Programs and Funds - Reporting Directly to UN General Assembly  

Economic and Social Council


Functional Commissions

  Specialized Agencies (autonomous organizations working with the UN and each other through the coordinating machinery of the ECOSOC at the intergovernmental level and through the Chief Executives Board for coordination (CEB) at the inter-secretariat level)
UNCTAD - United Nations Conference on Trade and Development

ITC - International Trade Center (UNCTAD/WTO)    ITC Resources

  Commissions on:

Human Rights
Narcotic Drugs
Crime Prevention & Criminal Justice
Science & Technology for Development     CTSD
Sustainable Development
Status of Women   WomenWatch
Population and Development

Commission for Social Development
Statistical Commission

  ILO - International Labour Organization
UNDCP - United Nations Drug Control Program   Regional Economic Commissions For:

ECA - Africa
ECE - Europe
ECLAC -Latin Am. & Carribbean

Regional Economic & Social Commissions For:

ESCAP - Asia and the Pacific
ESCWA - Western Asia

  FAO - Food and Agriculture Organization of the UN
UNEP - United Nations Environment Program       UNESCO - UN Educational, Scientific and Cultural Organization
UNICEF - United Nations Children's Fund       WHO - World Health Organization
UNDP - United Nations Development Program

         UNIFEM - Develop'mt Fund for Women

         UNV - United Nations Volunteers

         UNCDF - UN Capital Developmnt Fund

  Other Bodies

Permanent Forum On Indigenous Issues PFII

UN Forum on Forests UNFF

Sessional and Standing Committees

Expert, ad hoc and related bodies

  World Bank Group

IBRD - International Bank for Reconstruction and Development - better known as The World Bank

IDA - International Development Association

IFC - International Finance Corporation

MIGA -Multilateral Investment Guarantee Agency

ICSID - International Centre for Settlement of Investment Disputes

UNFPA - United Nations Population Fund   Related Organizations

WTO - World Trade Organization

IAEA - International Atomic Energy Agency

CTBTO - PrepCom for the Nuclear-Test-Ban-Treaty Organization

OPCW - Organization for the Prohibition of Chemical Weapons
  IMF - International Monetary Fund
UNHCR - Office of the United Nations High Commissioner for Refugees     ICAO - International Civil Aviation Organization
WFP - World Food Program     IMO - International Maritime Organization
UNRWA - UN Relief and Works Agency for Palestine Refugees in the Near East     ITU - International Telecommunication Union
UN-HABITAT UN Human Settlements Program (UNHSP)     UPU - Universal Postal Union
Research and Training Institutes

UNICRI - United Nations Interregional Crime and Justice Research Institute

UNRISD - United Nations Research Institute for Social Development

INSTRAW - International Research and Training Institute for the Advancement of Women

UNITAR - United Nations Institute for Training and Research

UNIDIR - United Nations Institute for Disarmament Research

      WMO - World Meteorological Organization
      WIPO - World Intellectual Property Organization
      IFAD - International Fund for Agricultural Development
      UNIDO - UN Industrial Development Organization
      WTO - World Tourism Organization (same acronym as the World Trade Organization)
Other UN Entities

OHCHR - Office of the UN High Commissioner for Human Rights

UNOPS - United Nations Office for Project Services

UNU - United Nations University

UNSSC - United Nations System Staff College

UNAIDS - Joint United Nations Programme on HIV/AIDS

      OSG - Office of the Secretary General

OIOS - Office of Internal Oversight Services

OLA - Office of Legal Affairs

DPA - Department of Political Affairs

DDA - Department for Disarmament Affairs

DPKO - Department of Peacekeeping Operations

OCHA - Office for the Coordination of Humanitarian Affairs

DESA - Department of Economic and Social Affairs

DGACM - Department for General Assembly and Conference Managment

DPI - Department of Public Information

DM - Department of Management

OHRLLS - Office of the High Representative for the Least Developed Countries, Landlocked Developing Countries and Small Island Developing States

UNSECOORD - Office of the United Nations Security Coordinator

UNODC - United Nations Office on Drugs and Crime

UNOG - UN Office at Geneva

UNOV - UN Office at Vienna

UNON - UN Office at Nairobi