As an adjunct to this, if large numbers interest you there's a really excellent and long-standing set of pages about them at http://www.mrob.com/pub/math/largen

As an adjunct to this, if large numbers interest you there's a really excellent and long-standing set of pages about them at http://www.mrob.com/pub/math/largenum.html http://www.mrob.com/pub/math/largenum.html which has some fascinating incidental detail and covers infinities as well as large finite numbers.