With orders of $25 or more, Amazon offers Prime members the ASUS High Gain 5Dbi Antenna, model no. WL-ANT151, for $4.41. This $10 mail-in rebate yields a net profit of $5.59. With free shipping, that's the lowest total price we could find by $10. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping starts at around $5.) This antenna extends your wireless network and features a R-SMA connector. Rebate expires April 30.