Since 1897 wordplay enthusiasts have been seeking an order-10 word square — a 10 × 10 array of letters whose rows and columns, read in order, produce the same set of 10 words. In English this is so difficult that it’s been called the Holy Grail of logology, but the task gets dramatically easier when we increase the vocabulary, and one way to do this is to admit words from multiple languages:

A  A  N  G  E  H  A  R  D  E  Dutch
A  P  E  R  N  A  S  E  I  S  Spanish
N  E  C  E  L  I  S  T  V  I  Czech
G  R  E  N  A  D  E  R  E  N  Norwegian
E  N  L  A  G  U  N  A  R  E  Spanish
H  A  I  D  U  C  E  S  T  E  Romanian
A  S  S  E  N  E  R  A  I  S  French
R  E  T  R  A  S  A  R  S  E  Spanish
D  I  V  E  R  T  I  S  S  E  French
E  S  I  N  E  E  S  E  E  N  Finnish

Graham Toal produced this example, as well as 775 others, in 2004, to prove the concept; Word Ways editor A. Ross Eckler estimated that Toal’s program might produce 135,000 such squares. In 2004 Toal told Eckler that some further efforts were being contemplated using distributed computing, but I haven’t seen anything since then.

(A. Ross Eckler, “The Polyglot Ten-Square,” Word Ways 37:3 [August 2004], 207-208.)