The chairs pictured above have made a "come back", as have many items designed and built in the middle of the last century. The graceful curves and lack of ornamentation allow ease of mixing with other periods of furniture, as well as fitting in nicely with their own period. The inclusion of this chair in decor as a counterpoint to more traditional classic furnishings can be especially beautiful---as described in this post from Acanthus and Acorn about Combining Classic and Modern.
In 1955, Verner Panton designed the single-form cantilevered plywood S-chair, which was developed in co-operation with Thonet, and for several years afterwards, he attempted to translate this design into plastic. Eventually, he achieved his goal with the revolutionary Panton chair (1959-1960), and in 1962 offered the production rights to Herman Miller. (Design of the 20th Century, Charlotte & Peter Fiell, Taschen, 1999.)
Photos of some of my favorite uses of this chair follow...Above: Kim's kitchen from Desire to Inspire
Want to buy a "Panton" chair or six? There are lots of places to find chairs like this, though the licensed Panton chair is available only through Vitra, and a bit pricey for many budgets at $1405/chair. There are many knock-offs out there that range in price from $299 to $80 per chair. You'll want to be sure and check stock to see if they carry your favorite color. There are even Junior chairs available for your style-loving kids!