One guy between me and freedom? seconds count? I'm gonn have to say some sort of feint, probably to the right, then a quick tenkan or other sidestep to the left, to get around him. Maybe some kind of atemi to the face as a distraction.Why close with the guy when all you want is to get around him?
Alternatively, I would open my blade, show it, and rush by him. I doubt he'd try to grab me. If he did, he might pull back a stump.

I would do a jab to the nose then a cross to the jaw and run like heck.

I think one needs to evaluate this scenario.I agree any strikes or kicks would be fine, a bloody mess good too, but, this may accelerate the fight, and have all members join the fight at once. If this is a serious threat to your life, and you want to really discourage the rest, I favour a strike to the throat. Everyone has all sorts of weapons, spear hand, shuto, tiger mouth,etc. I know this may sound harsh, but if you want to take the guy out, the throat is a good target. There was one suggestion....."I'm gonn have to say some sort of feint, probably to the right, then a quick tenkan or other sidestep to the left, to get around him. Maybe some kind of atemi to the face as a distraction.Why close with the guy when all you want is to get around him?"
This to me is a bit risky, when you get around him, now you got someone to your rear and he is not out of the picture. This sounds like an Aikido type movement and then deal with all the attackers.If you can hit him to distract him, hit him so he won't continue, forget the distracting stuff, not in this situation. It may work like randori in the dojo, but on the street, that just won't get the job done. The leader needs to be taken out, period, not just get around him, as his group will probably not attack 1 at a time, like the practice in the dojo.You need to make his associates really think about continuing the fight, after their main guy is spitting up blood or is laying there gasping for breath.

Senseilou, I agree that getting around him to fight the others would be foolish, but my understanding of the scenario described is that the buddies are on the other side of the road, distant enought that, if I can get by him quickly, I can run away like the craven coward i am. I can do a pretty good 800 yard dash with the proper motivation!
If the four other dudes were IN the picture, I'd have to go with a variation of the bloody screaming mess. I'm thinking low kick to the knee/shin/instep to get him to drop his hands a little, then follow up with an eye gouge or throat strike. If you CAN'T run from these guys, you need to make a horror show that will cause them to reevaluate. Honestly, though, I think you're going to the ER or the morgue if it's five on one.

Jamoni, I mentioned this in another post as well. The late Grandmaster James Mitose said if a coward comes to you and wants to learn not to be a coward, first tech him to run and be a good coward. Nothing wrong with running away if they will let you, but you may have to fight to get out of one of these situations

Double leg takedown/tackle...get up and kick him in the head a few times and ball out.

First I would pirouette through 360 degrees and then cartwheel to the left. I'd follow this with a back flip up and over my attackers head, landing behind him. I would then be in a position to pull his underpants up over his head, in a technique called a "wedgey". Whilst he was busy trying to extracate his knickers from his bum, I would quickly tie his shoelaces together and then push him over.

I would expect his freinds to be so impressed that they would burst into spontaneous applause, during which time I would make my escape. If that didn't happen I would fashion a weapon from a strand of hair and some snot, before commencing on a "Jackie Chan" like fight with them all.

What's that you say? That wouldn't work...all a bit too Hollywood? Well, it's as realistic as some of the other replies on here.

this will prolly sound kinda stupid in the perspective of some of you with nice, fancy, moves that have unpronouncable names. If i had to fight, I would try jumping at him and side kicking him(perhaps its called a jumping side kick, i don't know) either at the thigh, or somewhere between the stomach and nose. If i didn't have a chance to already leave without fighting.
Nice post Cato, nothig beter then a little humor to remind us to be realistic. 5 on 1? unless they're grade-schoolers or seriously handicapped(no disrespect to the young or handicapped), i think you'll lose if you try to go against that.