Brian Sullivan wrote
(in article
<1146082088.261714.57720@i39g2000cwa.googlegroups.com>):

Perhaps, but they vary based upon the size of those loosely
described "2-3 lenses".  The part about detaching the laptop
into a separate pack though I'm not sure I've seen anywhere.

You might start by taking a look at the various "CompuTracker"
packs from LowePro.  Here's a good place to look at them:

http://www.lowepro.com/Products/Backpacks/notebook_camera/

Brian,

Look here: www.kgear.com.  They have everything you mentioned but a complete
setup like you mention will be some what pricey.  This page will show you
how it all works: http://www.kgear.com/p/P450.html.

The nice thing is you can put all the parts together ala cart so you can get
only what you need.  Plus it's very modular so you can take only what you
need.  If you go this route I'd suggest a couple of shoulder straps along
with a holster for you camera.  This way you can slap on a couple of lens
cases and a shoulder strap and make a nice shoulder bag when needed.

I'm using their belt system (like it very much) and I'm seriously giving
consideration to adding a backpack.  On day I hope to get back to some
serious hiking and I'll need it.

I use the Lowepro Rolling CompuTrekker AW. Not only usable as a roller
carry-on, but you can wear it as a backpack. The laptop bag has a
shoulder strap and can hold a 15" laptop, but not my 17" PowerBook. No
problem there, though, because there is plenty of room for a 17"
neoprene laptop shoulder bag. So my wife uses the 15" laptop bag for
her ThinkPad. Plus, this bag has a built-in rain cover which I have
found handy here during the typhoon season. I do wish it was
detachable.

Although there is no detachable belt pack, it does have two small
accessory bags that could be hung on a belt. Personally, I use the
Lowepro Street & Field series waistbelt and harness when walking about.
Geeky, but handy. Really, though, the CompuTrekker is small enough that
I simply could just use that.

The only gripes that I have about it is that fully loaded it is just a
hair too thick for the overhead bins on some commuter jets. I have to
remove the computer or else leave the computer in the CompuTrekker and
pack the shoulder bag. Otherwise it is much smaller than the typical
carry-on and I have no trouble putting it under a seat or anywhere. The
other gripe is that the roller system and backpack straps combined make
it a little too heavy. A smarter choice would be to  make up your mind
and get the bag that will work the way you are actually going to use
it. Even so, it is real easy to load it up with gear heavy enough to
exceed the weight allowance for a carry-on, especially on some
short-haul foreign carriers.

PacSafe makes a number of gadgets that can turn these bags into
veritable fortresses. Handy when you want to leave the bag in your
hotel or in high theft areas like crowded airports, but probably
unnecessary in the field.

Then again, the CompuTrekker attracts absolutely zero attention. It
looks like just another one of those ubiquitous roller carry-ons you
see by the thousands in any airport. Most would-be thieves probably
assume it is just full of dirty socks and the like (and when I am
traveling, it often is, along with my camera kit -- just remove the
dividers you don't need and it works very well as a small overnight
bag).

I suppose you could also repel people by putting a durian in it, but
then they probably would not let you on the plane. :-)