Well, that might be one option, Talia. Treks 7500 ($660; trekbikes.com) is a bike thats definitely built for comfort. It has a very upright stem to keep that common bent-over biking posture to a minimum, a suspension fork and seat post to soak up bumps, and a cushy saddle. All in all, its a nice bike. Similar bikes include the Marin Redwood ($479; marinbikes.com) and the Novara Forza ($550; rei.com).
You dont say why youd rather not have a bike that puts much strain on neck and shoulders. Bikes certainly have ergonomic issues, but in a lot of cases these problems go away as your body adjusts to the different stresses and strains. While the bikes above try to eliminate some of those issues, its also true that they create new ones. Sitting very upright concentrates forces into the area of your butt, and that can be uncomfortable. And these are exceedingly pokey bikes; its really difficult to get much speed going when all but standing straight up. That may or may not be an issue, but I mention it just the same.
Dont completely overlook bikes that are comfortable but take a more balanced approach to their design. Giants FCR2 W ($700; giant-bicycle.com), for instance, has upright geometry and handlebars so you arent in that road-bike crouch, but its still a speedy bike, with fast wheels and a design that doesnt push your coefficient of drag off the charts.
But, if you have some real physical issue that youre attempting to work around, then you might want to abandon upright bikes altogether and get a recumbent. A recumbent bike puts you in a fully seated or supine position, with no weight at all on shoulders, neck, and arms. Theyre also quite fast on flat courses because they offer less drag than an upright bike. In the past I have mocked recumbents (all in fun, really!) because of their perceived geek-quotient. But they do solve some real problems with traditional bikes, and those who ride recumbents are uniformly enthusiastic about them.
One problem is cost. Recumbents are not mass-produced, so economies of scale are lacking. But theyre not too outrageous. A quality recumbent such as the Linear Mach III (linearrecumbent.com)can be had for around $1,500.
Check out Outside's picks for Gear of the Year and 400-plus gear reviews in the 2007 Summer Buyer's Guide, on newsstands now.