Bommer supports keyboard shortcuts to fill the rows or columns of a current selection. This works similar to the Fill row/column feature within Excel: when filling a row, it takes the leftmost selected value for each selected row and copies it across selected cells in that row; when filling a column, it takes the topmost selected value for each selected column and copies it down across selected cells in that column. Here’s an illustration of filling a column with a value.
To fill row(s), press Ctrl-R; to fill column(s), press Ctrl-D. Note that the leftmost or topmost cells do not need to be aligned. You can select a non-rectangular block of cells and still perform these functions.