I had an Applebred Duron 1800 - unlocked. Most of them overclock well due to their low voltage (1.5v), and that includes the 1400, 1600 and 1800 models.
My 1800 would hit 2200MHz on a cheap Asrock motherboard (which aren't even considered overlockers' boards). It only require +5% core voltage to run at this speed.
I did not mod this chip, because to be honest it did everything I asked it to and I had reservations about taking pot luck with cache integrity. The Duron is not the same as the Celeron, it's not really that much of a budget chip due to it's comparatively superior L1/L2 cache relationship. The Applebred can even slug it out against the P4.
As such I was running things like DVD Shrink, Far Cry and NFS Underground as well as Paintshop Pro. In fact, everything I loaded ran fast and multitasking was good. Compared to the 2.6GHz Celeron there was no choice especially in games, and when I upgraded to a Thoroughbred 2600+ (again unlocked, able to hit 2200MHz), there was a difference but it was less than I expected.
For most tasks I don't think you're going to be disappointed with that Duron. As suggested, if you raise the FSB speed (and hence the resulting core speed) then you can to an extent make up for the loss of L2 cache.
BTW this Applebred..I used it in a cheap system (around $240) for a a relative, and he was blown away by it since it was replacing his 2.6GHz Celeron - and this was at stock speeds. I did shed a tear inside when I let it go, though Links
Duron Applebred vs. Athlon XP Thoroughbred: http://www.madshrimps.be/?acti...rticle&articID=106
The day a Duron rode into Celeron County: http://www.anandtech.com/cpuch...howd...?i=1927&p=1
. AMD CPU Data: http://www.tomshardware.com/20.../amd...ult/page23.html
. Belarc Advisor: http://www.belarc.com/free_download.html
. GPU Comparison for Laptops: <a href="http://www.notebookche