Now we get to my personal favorite type of carry-on bag; the travelpack. What exactly is a travelpack? It's similar in philosophy to the home gym that allows you to do various exercises, or a cross-training sport shoe that allows you to go running as well as do aerobics. travelpacks are usually soft-sided, made of tough Cordura nylon material like regular backpacks. Most travelpacks look more rectangular than hiking backpacks or bookpacks (you may have heard the latter referred to as a rucksack). They look almost like soft-sided shoulder bags--until you unzip a secret compartment in the back that conceals a pair of backpack shoulder straps. These straps clip onto D-rings on the side (now bottom) of the bag, and you can now carry the bag like a back pack!
Some people don't like travelpacks for the same reason they don't like other all-in-one equipment; that is, all-in-ones are created to do many different things well, but not any one thing excellently. For example, while a travelpack does have shoulder straps, they lack the design that serious hikers and backpackers need (i.e. hefty waist straps, etc.).
Personally, I say "phhhhbbbttt!" to such naysayers. I have used my travelpacks in both shoulder bag and backpack mode--and they work really well for the majority of people. I also have the advantage of having a great-looking, modest piece of luggage that doesn't scream "hitchhiker!" like many backpacks do. I don't have lots of straps and buckles either, so if on the off chance I have to check the bag in, I don't have to wrap it in a plastic garbage bag like a lot of hikers do with their backpacks. While serious hikers and outdoor-types may not like travelpacks, I believe most people will find them plenty useful. Even those who are hardcore backpack enthusiasts, may find some models palatable (including the Eagle Creek Journey series, which look like regular backpacks).
The travelpack I used to use was a Jansport Daytripper; unfortunately they're no longer made. On my last trip, I used a small travelpack called the Sierra by Uphill Down (a review of this product is available in the Reviews section).
At the same time that I have seen an increase in travelpacks, I have also unfortunately had a fairly difficult time finding smaller travelpacks. Apparently, many manufacturers like to make them as big as the airlines will allow (which for me is now too big because I got so good at traveliting). I have spoken to the marketing department at Eagle Creek about this, because I think slightly smaller travelpacks (midibags?) are marketable, and a valid concern for smaller people (i.e. women, and those under 5'6"). There are a few smaller ones out there (the Sierra, and Jansport's new Carry On Pack come to mind) but they are few and far between.
Travelpacks are versatile, allowing you to look modest and civilized when needed, happy-go-lucky when you want. Most dirt smudges can be cleaned fairly easily with a damp cloth. Most of the manufacturers use reinforced seams so the pressure points at the seams don't fray.
Advantages: Looks modest and decent. Versatile; can be carried as a briefcase, shoulder bag or backpack. Easy to clean. Easy to mend with a small sewing kit.
Disadvantages: Most have no wheels so tougher for those with bad backs or trouble carrying heavy things. Extra bells and whistles usually means travelpacks are more expensive than a plain backpack or shoulder bag. And as mentioned above, most models are too large for women.
Important features to look for:
Continued: General Prices of travelpacks.