The number one piece of advice I usually give on the subject of lots of ancients is to expect culls--coins worth less than $1 belong in lots; usually with a couple nicer coins to help move the lots and hopefully dupe the novice buyer into paying too much for worthless coins. Thus, if you see a lot of "50 ancient coins!" but can only see a few nice coins on top of a whole pile, that pile is nothing but slugs and broken pieces of bronze disease.
One seller I have been following has perfected the art of this--they put 1-2 denarii and 2-3 nicer coins on top of a pile of culls, and usually does very well with them. I never bid on these until something possessed me to put in a bid on this one:
http://www.ebay.com/itm/Lot-of-71-A...4854?txnId=0Lot arrived yesterday, and I can honestly say that I am pleasantly surprised. Of the 71 coins, there were four keepers seeded in, and a few culls worthy of some further consideration. Now for the surprise:

Galba, 68-69 AD
AE Obol of Alexandria, Egypt
Bust of Galba right, SEPOVI GALBA AVTOK KAIS SEBA
Bust of Isis right, date LB, I assume indicating near the end of his very short reign?
Here is the other good one, and a first of the type for me:

Sassanid empire AR drachm, I think Khusro I, 531-579 AD. Very interesting design and will make a nice companion to my Gadhaiya Paisa which barbarized this design into abstract shapes and dots.
The other two keepers were a decent Maximianus II follis, GENIO POPVLI ROMANI, and a very nice Constantinopolis commemorative.
There was one gem among the culls, which I think warrants some further investigation:

It's either a barbarous late empire (good) or one of those miscellaneous usurpers or legitimate emperors of the 450-500 era (better). I think I may see -CIA- in the legend... maybe Marcian?