In a 7th century Strategikon, probably commissioned by the Byzantine Emperor Maurice, he describes his heavy infantry as being armed with 'Herulian swords', lances, slings, and, among other things, 'lead pointed darts'. My question pertains to the two weapons in quotes. What exactly is a Herulian sword? Is there some typology that can tell me which swords are Herulian?
Second are the lead-pointed darts. What would these look like, exactly? What part of the point would be made of lead? The blade? The tip?

Thanks for any input, because I'm quite in the dark on this subject.

Hmmmm.
Herulians were a tribe of Migration-era Germans, akin to the Goths. Supposedly originally from Scandinavia, they, like the Goths, had immigrated to southeast Europe and the Black Sea region some centuries before the demise of the Western Empire. Apparently, at one time, they had a fairly strong depredatory presence in the Balkans.
Since some Byzantine troops were equipped in the Gothic/Sassanian/Sarmatian fashion (at least the mounted Cataphractoi), this makes sense, from a certain point of view.
Not a clue as to what type of sword it would be, other than a double-edged, fairly long cutting sword of some kind, perhaps.

Lead-weighted (though not pointed, I would think) javelins were fairly common in antiquity, to increase their striking power at range.

Maybe it's something along these lines:
http://www.myArmoury.com/review_alb_mig.html
http://www.myArmoury.com/review_tmpl_suthoo.html

I also imagined the Herulian sword to be some sort of migration type sword that would work with the infantry formations described by the author. The Byzantine kit of that period was something that reflected the interaction with various cultures, but also became a model for Frank and Goth troops as well.

Agreed about the Herulian sword. As for the javelins, I would think the lead would be behind the point, perhaps around the socket. That way the weight and impact of the javelin would be increased, without making it unduly long, thick, and cumbersome.

Alexander;

Lead weighted darts, the lead somewhere between the middle of the dart and the point: Think of them as 7th century lawn darts rather than full sized javelins, although some early Roman Piliums were also sometimes lead weighted where the socket joined the shaft to the spearhead.

The Romans used these darts ( Plumbata ) 6 of them attached to the back of their shields .

Now as far as I know Plumbata are late Roman 4th or 5th century and I don't know for what span of time they were in use.

It's quite possible that the Byzantines continued using these long after the Western Roman Empire was no more.

I'm surprised that I'm the first to mention then as I'm sure that there are people here much more knowledgeable about Roman armies and their gear than I am.

Maurice recomended the use of the martiobarbuli, wether this was just another name for the plumbata described by Jean or a developed form has been hotly debated at times. The Martibarbuli was 12 inches long, had a feathered wooden shaft with an iron barded head and a lead wheight placed were the iron went into the wood.
Either way both of these lead weighed darts are truly nasty weapons, easy to use and doing a lot of damage against all but the most well protected targets. One interestign fact is that the Byzantines equiped botht their skutatoi (heavuy infantry) and thekataphraktoi/klibanophoroi (heavy/ extra heavy cavalry) with these war darts.