Ruger's P-series, as mentioned upthread are solid reliable guns.
Pros:
Inexpensive.
Utterly reliable.
Can take stupid amounts of abuse.
Can be used as a hammer (please don't do this while it is loaded) without any significant ill effects.
Sufficiently accurate for most self-defense and combat purposes.
Magazines widely available.
Easily stripped and cleaned without tools.
Cons:
Tend to be a little on the larger and bulkier side for their calibers and ammo capacity.
Ammo capacity often a couple rounds fewer than the competition (starts to be rectified with later models)
Trigger action not as slick as higher priced competition, but works just fine and gets the job done.
Not "match accurate" or intended for formal match shooting.
No parts to make competitive in IPSC/IPDA shooting.
Due to less 'sex appeal', aftermarket enhancement parts are not as plentiful as most other makes.
And if it matters to you, they're all double action. Most people don't care.
Bottom line: If you want a reasonably priced reliable work-a-day gun that will always get the job done as advertised, you could do a lot worse for a lot more money. (Beretta, I am looking at you.)
If you want a super-high-precision match gun, look elsewhere. If you just want a gun for self protection or plinking at a reasonable price and the Ruger product fits your hand, buy it with confidence. It will work just fine; Ruger's philosophy is reliability uber alles.
Only one caveat - the early P85s made from 85-90 are subject to a safety recall due to undersized controls and a fragile firing pin, remedied by replacement parts (Ruger will do this and any other parts failure repairs for free) as well as at the factory in the P85 Mark II and the P89. Most of them have long since been sent back to the factory and been repaired, but should you pick one up at a good price, you should call the factory (800-424-1886) and run the serial number by them to find out if it has been serviced. Also, the early P85s sometimes had inconsistent accuracy due to a two-piece barrel. If you can shoot it prior to purchase to check accuracy, the early P85 can be a stunning bargain (I picked up a good used one a few years ago for $200 from a private seller), but if you can't shoot your potential purchase then stick with P85 Mark IIs (stamped on the slides) or go with the P89 and later and you won't go wrong.
In case you're wondering, I gave the P85 away to a friend who really, really, really liked it but didn't have money for a defensive firearm of her own.