Feature request: provide more variables like [Today] to assist in filtering views

I've done a bit of searching, through your documents, but can only find reference to two such variables: [Me] and [Today]

Would be really nice to have some functionality available to filter views such as
Required Date < [Start of next month] and Required Date >= [Start of this month]
or
Scheduled Date < [End of next week]

Using [Today] +/- nn goes part of the way towards this, but obviously adding 7 days to [Today] is very different depending on whether you are running the query on a Monday or a Friday.

Given that most organisations work on a calendar week / month basis, I would imagine that this would be a popular enhancement.