I'm with Nemo and John W. on this one. Offhand I don't remember whether I've used "alas" or not, but I would do so without compunction if the situation seemed to warrant it.
(Incidentally, I just got my hardcover copy of
Anterooms today, in which Mr. Wilbur writes of "Shocked faces that,
alas, / Now know me for an ass.")
Just for fun I ran a
New York Times online archive search on instances of "alas" from the Times. Even limiting the search to the past thirty days (is that current enough for you?), there's no shortage of hits:
"The festival’s other defining element,
alas, cannot be brought to New York, and that is its special setting, the town of Risor."
"Mr. Harris, the 'How I Met Your Mother' star, who has previously served as the host of those first two awards ceremonies he mentioned, must,
alas, continue to wait to complete that personal triple play."
"
Alas, that power went to their heads, and filmmakers indulged themselves into a creative dead ends ('At Long Last Love') and financial calamities ('One From the Heart')."
"
Alas, that did not stop him from soon becoming a consultant to one of the most leveraged banks of all, Lehman Brothers."
Most of these (with the exception of the Neil Patrick Harris one) aren't especially jocular in tone, either.