| Space_com_-_The_Greatest_Myths,_Hoaxes_&_Mysteries_in_Astronomy_and_Space_Science Article briefly discussing 21 topics. |
| Stars_and_Planets Information about interesting stars and planets in our galaxy, as well as astral bodies outside the Milky Way. Includes photos. |
| Planetary_Phenomena Historical account of conjunctions, occultations, and transits 3000 BC to 3000 AD. |
| Air_Movement_and_Control_Association Provides publications, membership, certified ratings program and seminars for manufacturers of air system equipment including fans, louvers, dampers, air curtains, airflow measurement stations, and ac |
| Chartered_Institution_of_Building_Services_Engineers_(CIBSE) UK-based institution for building services including heating, ventilation and air conditioning. |
| Cooling_Technology_Institute Nonprofit self-governing technical association dedicated to improvement in technology, design, performance and maintenance of cooling towers. Membership, publications, certification, and meetings. |
| Eastern_Michigan_ASHRAE Newsletter, calendar of events and the contact to the society's officers. |
| South_African_Institute_of_Refrigeration_&_Air_Conditioning Site gives details about the organisation including training courses, journals and data manuals. |
| The_Wichita_Chapter_of_ASHRAE This site describes the activities of the Wichita, Kansas chapter of the ASHRAE. |
| University_of_Illinois_at_Urbana-Champaign Student chapter overview, news, event and activity information, design projects, member resumes, officer list, mailing list, and membership information. |
| The_Aesthetics_of_Symmetry A brief digression into how people perceive symmetrical patterns -- what makes them boring, interesting, or overly intricate |
| Back_to_Square_One Includes description, solutions and other resources on this cube-like puzzle. |
| Critical_Math Articles and images on recreational math from fractals and magic squares to mathemorchids and Galois. |
| Cryptarithms_Online 70 brain-teasers; a Primer on Cryptarithmetic; books and links to alphametics on the Web. |
| CuriousMath Include news, math tricks, methods, facts, trivia, mostly posted by users. |
| David_Singmaster__List_of_Available_Material Teaching and recreational items in this personal collection. |
| The_Diamond_16_Puzzle New version of the classic puzzle using row/column/quadrant permutations to display symmetries of graphic designs. Has link to a site on the underlying mathematics (Diamond Theory). |
| A_Disproof_of_Pythagoras\'_Theorem? A method of disproving the Theorem of Pythagoras is presented. The author is adamant that this is intended only as a puzzle to find the mistake in the arguments, and not as a serious proposal. |
| The_Eugène_Strens_Recreational_Mathematics_Collection A special collection at the University of Calgary, including the archives of Martin Gardner. There is a searchable online index. |
| Eureka The annual journal of the Archimedeans, the mathematical society of the University of Cambridge. It regularly contains articles on recreational mathematics. |
| Fair_Dice Contains a complete list of all possible Fair Dice, most of which are not cubes. Includes pictures. |
| Famous_Curves Visual animations of famous curves. |
| Fast_Arithmetic_Tips Three categories: defensive - know to check an answer, offensive - fast mental calculations, and math magic. |
| Fibonacci_numbers_and_the_Pascal_triangle The relation between Fibonacci numbers and Pascal's triangle. English/German/Serbian. |
| Final_Answers Numerous facts including formulas, magic tricks, fallacies, recreations compiled by Dr. Gerald P. Michon. |
| Fun_With_Mathematics Includes pages on the topics of primes, fibonacci numbers, PI computation, data encryption and links to calculator programs. |
| Gardner_Index Rough index to the fifteen books containing Martin Gardner's Mathematical Games articles from Scientific American. |
| Geometric_Packing_Problems By Joseph Malkevitch: "Given one shape X how and when can one pack identical copies of this shape into another shape Y?" |
| HAKMEM A collection of problems from MIT. Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program. |
| How_To_Manually_Find_A_Square_Root The way to do find a square root without a calculator. |
| Iamond A page on polyiamond puzzles. Includes many pages on tessellation. |
| Jlpe\'s_Number_Recreations_Page Features original number recreations by the author, such as generalized perfect numbers, digital diversions, diophantine equations, didactic numbers, and number theory. |
| Look_and_Say_Sequence_Generator Creates a special kind of summation formula created by John Conway. |
| MAA_Library_List_in_Recreational_Mathematics Book list split into categories. Includes title, author, publisher and date information about each book. |
| MAT_007_I_News A newsletter edited by undergraduates of the Department of Mathematics at the University of Toronto. Includes some online copies. |
| Math_Forum__2001_Mathematics_Game A contest that asks to write all integers from 1 to 100 using only the digits 2,0,0,1 and arithmetic operations. |
| Math_Forum__2002_Mathematics_Game A contest where the contestants have to write all integers from 1 to 100 using only the digits 2,0,0,2 and arithmetic operations. |
| Math_Forum__Algebra_Problem_of_the_Week View this week's algebra problem or those of previous weeks. |
| Math_in_the_Movies A guide to major motion pictures with scenes of real mathematics. |
| Math_Magic_By_Computer Interactive java puzzles and activities in different mathematical topics. |
Astronomy/Astrophysics on the Internet