Seagull Infrared Flash Remote Trigger for Digital Camera SYK-3

Pros: It does what it says. When it sees a flash, it fires. It fits on my tripod.
Indoors, it fires consistantly without problems.
Even though this model doesn't support pre-flashes, I have had moderate success when leaving pre-flashes enabled on my Nikon D70s.

Cons: Outdoors, if the sun can see the trigger's eye, then the chance of it working is low. Works well when the eye is shaded, though with understandably limited range.
When connected to my SB-600 flashes, the connection is very loose. It can be disconnected without releasing the hotshoe lock.
I had to tape an area of the trigger's hotshoe. Since it is loose, one pin on my SB-600 was making contact and setting off the flash when moved or bumped.

Other: A good buy. For the amateur, the price definitely beats buying PocketWizards (or other radio triggers), and you get the same effect in most cases.
You don't need SYK-4 or SYK-5, this one will do, as long as you understand how to light manually.

Pros: Very basic and cheap remote trigger. Works fine for my intended use. I use it together with flash SKU 11402 with good results.

Cons: Nothing really if you know what you are getting, there are no settings, can't do pre-flash but. Cheap unit so range is limited, but if you need that you should look at radio trigger units.

Other: Fun for doing experimental stuff, with the low price you can get several and trigger all your flash units. I have a setup with three "off camera" flash units and can make some fun lighting setups.

Pros: Confirmed working with Nikon SB-26, SB-27 (trigger voltage of 4 volts), Black's ST 45 flashes (trigger voltage of 70 volts).
The hot shoe fits well with all above flashes.
It's quite sensitive indoors. Sensor does not have to face the triggering flash. Reflection from walls/furniture will be enough.
Both the FEL (flash exposure lock on Canon) and a -2EV main flash can trigger it.
I use canon built-in flash to trigger it. Set the FEC to -2EV.
Each shot, I have to press FEL, then hold and press the button. So two flashes will occur. This is to get around the TTL pre-flash problem.
Alternatively, you can mount a manual flash on Canon (or tape over the camera hot shoe data contacts, and put a Canon flash on as a dumb manual flash). That way, you don't have to use FEL.
It's not a good idea to use a hand to cover the built-in flash when pressing FEL. Because while it avoids the FEL triggered flashes, it causes the camera to overcompensate (because it sees inadequate light) to put out full power in the main flash. That will not only mess up your shots, it will make the built-in flash very hot and damage it if you do this nonstop.

Cons: When used on Canon 430EX, the flash will lock up after a single flash. Pressing the flash test button does not reset it. You must power off and on the flash.

Other: Best price, works as expected.

Pros: Easy to set up -- just slide on a flash and you're done. There are no batteries, no cables, no switches, no ANYTHING. It is amazingly simple.

Cons: As others have commented, it is sensitive enough to detect the pre-flash that most modern cameras use. Thus, it triggers on the pre-flash, and misses the actual exposure. There are things you can do to adjust for this, but that limits the usefullness quite a bit.

Other: It is a good addition to all those extra flashes you have lying around, but you'll probably find it too limiting for any serious work.

Pros: - really low price. At other places you pay twice the money for it.

- works as it is supposed to

- easy to use, not much you can do wrong

Cons: none so far

Other: Great product for a little price.
Gives you the chance to improve your photos without spending tons of money.

Pros: Cheap and useful. Very easy to use. Triggers all the flashes in my bag. Synchrone is very good, works with paraflash in good synchrone.

Cons: Could be better build quality.

Other: Buy it, never regret what you get. Worked with my 1970 made Osram flash and old SB series Nikon flashes. Synchrone is very very good, worked with my Hensel 5OOC paraflash in good synchrone.

Pros: Slave triggers that employ the use of another flash to trigger the connected flashgun are fairly simple pieces of gear. With the electronics, there's really not that much variation between similar products and most differences arise in mechanical construction. These units are built extremely well and I've had no trouble using them with larger flashes, atop umbrella brackets and such, using them on location when radio triggers weren't needed.

Cons: Well....it doesn't come with a second, sexy wife or knowledge of what the deepest meaning of life and existence really is, but for the price, you just can't go wrong.

Other: Don't think, just order a handful today and start enjoying off-camera flashing right away.

Pros: Small, light, does exactly what it says and it's cheap. Tried it with my nikon sb400 and used the built in flash, triggered every time. I bought a yinyan flash to be used with this and it's great.

Cons: None that I can think of, it only has one job to do and it does it.

Other: If you want a slave trigger to compliment your other flashes, just get this.

Pros: Cheap and lightweight, therefore perfect for secondary flashes - when attached to SKU 11402 loaded with 2*AA NiMH rechargeable batteries, the resulting secondary flash is only 170 grams!

Cons: The light sensor (phototransistor) is not well centered in all three my items, thus reducing sensitivity (doesn't really bother, because I use these triggers for secondary flashes, which are installed close to the object being photographed).
Lacks fixing nut at the bottom mount.
The schematics are really primitive, so it could be cheaper.

Other: If you need reliable triggers for secondary flashes - these are a good choice.

Pros: I have another optical slave trigger that looks exactly like this one, however it cost me $30 before I found out about DX! Spewing.
It has a high tolerance to strong outside sunlight and can still trip the flash. The metal foot for the flash to clamp on is solid and hasn't come loose in the 12+ months I have been using it.

Cons: if I had to pick anything. I would say it is a little on the large side. Which isnt a massive negative. I have another optical slave that has a more slimline appearance. Makes for better ease of use when putting the flash in a tight spot.

Other: I keep it in my bag incase my other flash triggers fail. It also lets me trigger another flash without an expensive 4th Pocket Wizard :)