RFSim99 is a free linear S-parameter based circuit simulator offering schematic capture, simulation, 1 port and 2 port S-parameter display and file support, tolerance analysis, stability circles, and much more. Requires Windows 95, 98, NT or 2000. File size 2045K

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Qucs is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window.
Link to Qucs site

The following limitations apply to the EAGLE Light Edition in general:
•    The useable board area is limited to 100 x 80 mm (4 x 3.2 inches).
•    Only two signal layers can be used (Top and Bottom).
•    The schematic editor can only create one sheet.
Apart from these three limitiations the EAGLE Light Edition can do anything the Professional Edition can do. You can even load, view and print drawings that exceed these limits!
 Link Eagle Printed Circuit Freeware