When contemporary art starts selling like hotcakes, it's time to forego gallery walks in favor of more exciting forms of entertainment, like, say, stamp collecting. This is because a flourishing demand for contemporary art is a sure sign that the work is getting dumber or, at least, that the buyers are getting smarter. Either explanation is cold comfort to the tradition of radicalism in art: Blahniks don't belong in the studio, and neither do hedge-fund managers. Both, however, would seem to be in ample supply: Contemporary art, as a market segment, has more than tripled in value over the last 10 years, and while there's no established metric tracking gallery sales, anecdotal evidence points to a boom of unparalleled proportions.Much of this new work is urbane, sophisticated stuff, calculated to let the viewer in on a very exclusive joke. (Look! A painting that makes fun of painting! Get it?) It's also self-referential, needlessly recondite, and dull. It serves as an anesthetic in a culture replete with visual sedatives. I ask you: Given The O.C. and the movies of M. Night Shyamalan, do we really need the paintings of Damian Loeb?Luckily for us-that is to say, we who like our art to make a point, preferably articulated in a language we might understand-an antidote has emerged. A new generation of artists is reintroducing the outside world to art-making and, in the process, making art relevant again to the outside world. The term "political art" carries unfortunate connotations. Sadly, we've come a long way since "Guernica." Until recently, all that was left of the genre were shrill bromides and race/gender/sex-based pieces. But a cadre of new artists whose work is informed by politics-Natalie Jeremijenko, Trevor Paglen, and collectives like the Critical Art Ensemble, to name a few-are far less pedantic, and as such, defy lazy categorization.It would be a mistake to anoint this a school, but the artists do share many characteristics. They do not, generally, hail from hipster academies like Cal Arts, UCLA or Yale; the artwork is usually long on humor and short on pretense; and the artists employ expertise gained from backgrounds in far-flung academic disciplines. Jeremijenko, for example, nearly obtained a doctorate in engineering, and Paglen is an "experimental geographer" at the University of California at Berkeley.Though working in different mediums and toward different goals, what they share is an element of what the French call engagé, which roughly translates as: giving a shit about something other than theoretical hermeneutics. This new crop of artists has managed to avoid the pitfalls of what rendered even the best of the '80s work shrill and, worse, ineffective. Instead of being didactic, it's fun. This only sounds like a contradiction in terms.Natalie Jeremijenko's work feels-and I mean this in the best of ways-like it was created by a precocious-but-irretrievably-silly 8-year-old. She is deeply concerned about the environment, and to demonstrate the deleterious presence of PCBs close to our urban centers, Jeremijenko repurposed a litter of $30 toy robot puppies, replacing their snouts with pollution detectors. Set free in a landfill, they homed in on the worst sources of the pollutants, gathering around them and yipping their inane, tinny, toy-store bark. It's clever, and funny, and scary. Jeremijenko brings her varied background to bear in her work. She spent her formative years promoting rock festivals and working toward a Ph.D. in electrical engineering. Small wonder her projects, like the one where six trees are planted upside down, roots to the sky, feel like science projects run amok. Jeremijenko is just one of a host of artists that bring a disparate set of tools to the making of art.Let's call them "art scientists," for the excellent reason that many of them hold down real jobs in real science departments-like Paglen. He transcends political pranksterism to create data-based conceptual works that contain not just a message, but original research of value to multiple disciplines. Snoring yet? Stick with Trevor-he's worth it: In "Torture Taxi" he obtained the flight information for the private CIA jets that shuttled terrorist suspects to unsavory regimes. With this work, released in book form with plenty of graphs and visuals, Paglen accomplishes a feat of investigative journalism and geography that also somehow functions as art-if you need to call it that.The Critical Art Ensemble is probably the best-known group of artists in this area. The collective has been releasing a stream of books, performances and video projects since 1987, much of which traffics in a genre it calls "Bio-Art." The five artists came to national attention in 2004 when one member, Steven Kurtz, was arrested by federal agents for violating the Biological Weapons Anti-Terrorism Act. Kurtz had been cultivating bacteria for an upcoming show at the Massachusetts Museum of Contemporary Art. The case against him became a cause célèbre among civil-liberties groups and politically engaged artists and has, in its way, made the CAE all the more effective in getting its message out.Unlike so much of what's been created in the last 20 years, this feels relevant. It matters-to say nothing of street art, which is political in the very nature of its exhibition. In the '80s, the art world briefly flirted with graffiti art. We've all seen Basquiat, so I won't bore you, but let's just say the art world woke up with a hangover and flagged the next limo to 57th St. So it's a delicious irony to watch "street art," as it's been rechristened, become more culturally relevant than the art market that shunned it. The graffiti blog Wooster Collective gets nearly as many page views as the all-things-art-world portal Artnet.comThis brings us to that idée fixe of our age: But is it art? After deep pondering, I think I have an answer: Who the fuck cares? It's funny, and somehow deeply moving and, unlike a trip to any number of galleries, transformative.All these artists occupy what I think of as the post-Abu Ghraib art world: The now iconic figure of a shrouded form, splayed Christ-like atop a pedestal, changed the nature of representation forever. Not because of the political charge the image carries, but purely for the objective power it possesses. As the critic Arthur Danto puts it, the Abu Ghraib photos raised the bar, and "must from now on act as standards against which we can judge the political efficacy of art."