Yes, absolutely! You can use conditional formatting based on the WEEKDAY function in Excel to format cells depending on the day of the week. Here's how:

1. Select the cells you want to format.

2. Go to Conditional Formatting. Navigate to the "Home" tab and click on "Conditional Formatting" in the Styles group.

3. Choose "New Rule."

4. Select "Use a formula to determine which cells to format."

5. Enter the formula in the format box. The formula will use the WEEKDAY function to check the day of the week for the date in the cell. Here are some examples:

* To highlight weekends (Saturday and Sunday), use: `=WEEKDAY(A1,2)>5` (Replace A1 with your actual cell reference containing the date)
* To format cells for Mondays, use: `=WEEKDAY(A1,2)=2`
* To format cells for any specific day (replace 2 with the corresponding number for the day: 1=Sunday, 2=Monday, etc.): `=WEEKDAY(A1,2)=[day number]`

6. Set the formatting. Click on the "Format" button and choose the desired formatting options (e.g., fill color, font color) for the cells that meet the formula condition.

7. Click OK.

Now, the cells will be formatted based on the day of the week according to your formula. You can create multiple conditional formatting rules with different formulas to format cells for different days or criteria.