It's generally considered to be a solid old rifle.
There are a few rare, collectible variants out there, but most of them you'll run across are fairly standard with no premium placed on the value.
It filled the same role for the Russian infantry (and a handful of other countries) that the M1903 Springfield did in the USA, the M98 Mauser for Germany or the Enfield 303 did for Canada, Australia and the UK.
If it's still in it's original chambering it fires the 7.62x54R, which ballistically is comparable to the 30-06.
It's a bit longer and more unwieldy and the action isn't quite as smooth and fast as it's aforementioned counterparts, but they're still not a bad piece of hardware, assuming you get one in good working order.
Accuracy is not usually considered as high as the others either, but don't tell Vasily Zaitsev.
In reality, between all these rifles I mentioned you'll see a much bigger difference in speed and accuracy based on who is shooting it, than which rifle they're shooting.
In the early and mid 90s, there was a massive importation of foreign military surplus SKS rifles, and they could be had all over the place for $99.
In the late 90s and early 2000s, the M96 Swedish Mauser in 6.5x55mm was the new kid on the block. It's numbers weren't as high as the SKS, and ammo was never as plentiful or cheap, but the prices on the rifles were low enough to get some decent quantities of them onto the US market.
Most of the big stockpiles of those two have now been exhausted, so they fetch slightly higher prices now.
These days the Nugget (short for Moist Nugget, a nickname of the Mosin Nagant) is the big item the importers are banking on.
Early in the boom, you could get them as low as $49, although for several years the prices remained fairly stable between $79 and $129.
Those prices assumed they were in functional condition and had at least a halfyway decent bore (many will have some degree of pitting) and proper headspace. If not, the prices were usually lower.
Unlike the SKS or M96, most of these surplus Russian rifles were heavily used, so the wide price bracket was a reflection of the varying grades that were available for sale.
I haven't checked lately, but it's been imported for enough years now that it wouldn't surprise me if the stockpiles of those are drying up too, which should mean an increase in prices.
There are several forums and collector's sites dedicated to these specific rifles.
Some can help you identify if your rifle is in it's original configuration, the arsenal and year of it's manufacture, and it's value.
I'd suggest doing a search on those sites for more information.
Here are a few to get you started:
http://7.62x54r.net/MosinID/MosinID.htmhttp://7.62x54r.net/Forums/index.php?board=1.0http://www.mosinnagant.net/***The aforementioned advice was given by an opinionated, half-senile armchair commando and should not be trusted implicitly for it's accuracy.