Wabbitemu - Wabbitemu is an accurate emulator for Texas Instruments based calculators TI-73 to TI-86.
Emu48 - HP38/39/40/48/49 Emulator
CEmu TI 84+ CE Emulator - Emulates the TI 84+ CE and TI 83 Premium CE calculators from a ROM dump from a real calculator.
TilEm - TilEm is a TI Calculator Emulator that uses Gtk. It supports:
meta-calculator - The most sophisticated and comprehensive graphing calculator online. Includes all the functions and options you might need. Easy to use and 100% Free!
AlmostTI - AlmostTI turns your Android device into a Texas Instruments graphing calculator.