Nowadays, the question of potential industrial applications of new materials plays a major role. The peculiar physical properties of quasicrystals certainly give rise to the hope that they may become of some practical importance in the future. Today, mainly three fields of applications are discussed, and partly have already been realized. For more details, see also [B:Dub, B:SD, R:Dub].
The most important area of applications concerns the use of quasicrystals as materials for surface coatings. This is favoured against the use of bulk material because bulk quasicrystals tend to be rather brittle, while coatings benefit from the hardness of quasicrystals. This is also reflected by the fact that at least two international patents [P:DW, P:SGAEMS], and thus the only patents related to quasicrystals that the author is aware of, have been issued for methods to produce quasicrystalline coatings. The most prominent example is the use of quasicrystalline coatings in frying pans - an application that is famous in the quasicrystal community since for years it has served as the key example without any quasicrystalline frying pan being commercially available. Nevertheless, due to their particular physical and chemical properties, quasicrystalline coatings are well suited for this kind of applications, and they are also rather cheap which makes them even more interesting for industrial applications. Just recently, quasicrystal-coated frying pans appeared on the market, they are now sold by the French company Sitram under the trademark Cybernox, see e.g. http://www.inductionsystems.com/cookware/cybernox.htm. Usually, you will find that the term "quasicrystal" is not mentioned at all in connection with this product - apparently the company does not really trust in the attraction of this term.
A different way to circumvent the brittleness of quasicrystalline bulk material while preserving some of its useful properties is the utilization of an Al-based alloy (typically Al-Mn-Ce) reinforced by precipitation of icosahedral particles in the nanometer range. Such materials, which are now commercially available in Japan, are of great technological interest because they can be very strong but much lighter than other materials with comparable physical properties [IK97, IKSK98, XELS99]. Examples of applications that have already been realized are razor blades and surgeon's instruments, though this may have been more by chance than being an intentional application of quasicrystals. Anyway, if these materials can hold what first examinations promise, see, for example, [IKSK98] - the one and only paper in the "applications" section of [B:TF] - and references therein, they will undoubtedly find their way to applications in many different areas, such as the aviation industry for instance.
A third, and maybe more speculative, application concerns the use of quasicrystals as a reversible storage medium for hydrogen. The most promising quasicrystal materials for hydrogen storage are Zr-based quasicrystals, see the conference reports [CKGV+98, KKMG+98, KZME+98, NJMD+98] and references therein, and also [CVGK+97, TNAM97, WMKA+97, KGK98, NJBL+98, SMBG+98, VMSK+98] for recent work on this subject. For such systems, storage capabilities of almost two hydrogen atoms per metal atom have been reported, comparable to the storage capability of the Ti-Fe hybrides which have already been applied in non-polluting internal combustion engines. Further investigation are certainly needed in order to reach the stage of industrial applicability.