Calc's Random Number Generator (accessible via Sheet - Fill Cells - Fill Random Number) allows to generate random values that will be applied to the selected cell range. This means that you need to manually select the range where the numbers will be placed. The problem with this is when you want to create many random numbers at once, for instance 10,000 rows by 50 columns. It's a really bad experience to select such enormous range manually. Instead, we should allow the user to enter how many columns and rows to generate from a starting selected cell. This would be similar to what Excel does (not exactly, but similar). See attachment 186746 [details] from bug 154872 for a comparison between Calc and Excel RNG's.
Shift+Ctrl+T A1:AX10000 Enter 50x10000 range gets selected ;-) But yeah..