such as the one from Cobaltcable.com http://www.cobaltcable.com/product/bi-wire_jumpers.htm
Does it make any different as it's expensive....
Since you're curious whether it will make a difference, I'd try replacing the jumpers with some cable you already have first before committing any money to something that you're not sure will make a difference.
I replaced the jumpers on my old speakers with short lengths of 14-gauge wire I had laying around. I didn't notice any difference.
AF, although there's a delusion about "crappy jumpers" floating around on some audio forums, neither Ian nor any other competent speaker designer would sabotage their own speakers by putting on jumpers that would harm the performance. The brass used in the jumpers has a somewhat higher electrical resistance than pure copper but this is totally meaningless over the 2-3" distance involved. What this myth does do is to provide yet another opportunity for charlatans to prey on the gullible by peddling a connection a few inches long at an outrageous price.
As much as I like to disagree with JohnK
I'm with him on this one. There is no way that anyone can convince me that a 3 inch run of wire or brass etc is going to make any audible difference in sound.
The only other option is to "bi-wire".............but, as was pointed out to Me in a previous post....that will only "move" the "split" closer to the amp.
Is that better?....................to each His own.
I do not know if you could hear any differences with speaker jumpers, probably not, but on my HK 3480 stereo receiver it was a night and day improvement after I'd ditch the POS jumpers and use a decent quality RCA instead, check this out:
http://forum.ecoustics.com/bbs/messages/1/106339.html
I just went to that cobaltcable website to check out those speaker jumper cables...holy smoke...$40!! go to your local audio shop or home depot and get some 10~12ga wires then connect the spades yourself!!
In reply to:
that will only "move" the "split" closer to the amp.
I'm still proud of myself for
coming up with that one. 
If you like cool looking cables, check out these "pure silver" jumper cables for about $37: http://cls.audiogon.com/cgi-bin/cls.pl?accstwek&1102608804
For bragging rights and If you have tons of money to burn, try some of these $600 jumper cables:
http://cls.audiogon.com/cgi-bin/cls.pl?cablspkr&1104005597
There have been many companies that provide "esoteric" cables of different materials - Van Den Hul made a carbon fibre cable.
There are many expensive mfg'ers on the market, with Pierre Gabriel (Jadis) being one of the broadest in terms of products.
http://www.jadis-electronics.com/pages_eng/produits/menus/index_produits.htm
http://www.pierregabriel.com/PierreGabriel/Page/CablesIntro.htm
NOTICE - this is not a reflection on my views, simply a statement of fact. While I have "audiofile leanings", I am not a believer in beyond belief cable hype. LOL
Oh-oh, You mean You "came up with that?"...........I THOUGHT that I was quoting audio fact, from this site.
Seriously,.......I STILL like it.....very plausible.
In fact, here's one of mine..........
How about if someone just calls Axiom, and orders another pair of jumpers?......two, "sandwiched" together....or maybe three pair...creating a "thicker" signal path.
heh heh