A good antenna for broadcast FM radios:

        The following is a description of a J-Pole antenna made from 300 ohm
        TV twin-lead. They have quite a few advantages which include improved
        performance over simple dipoles, portability, and low cost.
 
                        |   | do not short this end.
                        |   | (when trimming for vswr, cut both sides)
                        |   |
                        |   |
                        |   |
                    3/4 |   |        Technically-speaking, this is a 1/2
                   wave |   |        wave end-fed antenna with a 1/4 wave
                        |   |        matching section.
                        |   |
                        |     1/4" gap
                        |   |         (trim for vswr _below_ gap)
                        |   | 1/4
                        |   | wave
                        |   |
    coax ctr conductor=>*   *<= coax shield
                 1 1/4"-|   |
                         -*-    solder the twin leads together at bottom
 
        For a center frequency of 100 MHz:
        1. Start with @80" of TV twin lead (flat, NOT foam core)
        2. Strip 1/2" of insulation at bottom and solder wires together.
        3. Measure 1.9" from soldered wires and strip insulation on both
           sides. This is the solder point for a coax feedline.
        4. Measure 24 1/2" from coax shield solder point and cut out 1/4" notch.
        5. Measure 73 1/2" from coax center conductor solder point and trim
           off twin lead at that point.
        6. Feed with a length of RG58U or RG174U (50 ohm) coax.  Tape coax at 
           feedpoint to the twin lead for strength and seal coax for weather
           protection.  Make a few turns of coax about 2" in diameter to 
           form a choke to keep RF off the coax feedline.
        7. Use a balum to get from the coax to a balanced input on an FM
           receiver (There will be some mismatch, 50 vs 75 ohm, but
           receivers are usually not that precise on input impedence anyway.
        8. Lay it horizontal (FM broadcasts tend to be horizontally
           polarized)

Built the above, and I am using it to listen to 92.7 WDRE Garden City, NY
in my apartment in Bridgewater, NJ (Rt 22 & Rt 202/206, near I287).
Distance about 50-55 miles.  Yes, some hiss, but quite listenable
considering the distance.  Also, there is a co-channel country and western
station that I happened to null out enough to let my receiver capture
the desired station.  I lucked out that a good location for the antenna
was in back of a bookcase on the floor, out of sight.
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Above diagram and instructions adapted and edited by me from N5RCK's posting
on rec.radio.amateur.misc