“Another Deal Site” via Amazon has the Canon Speedlite 90EX for $41.42. This is the lowest price we’ve seen for this flash.
It is from a third party seller but fulfilled by Amazon, free shipping from Amazon US warehouses, and the seller has perfect reviews. It is white box and likely import as well.
Some find this Speedlite useful for fill flash, but our favorite use is as a really cheap wireless flash master (for 5D Mark II/III or 6D). At $41.42 it’s a fraction of the cost of the 270EX II ($169) or a real transmitter (ST-E3-RT, $278). There are some downsides — low battery life, no red AF-assist light — but at this price it can’t be beat!