"Inverting" a table, OLAP-style

I have a data-collection app, which creates a table like this, more or less:

t timestamp
name varchar
value numeric

the number of distinct values of <name> is 800 and growing, besides being
data-dependent, so it might be pretty inconvenient to have a single table with
800 columns. (and we might exceed the 1600-column limit someday)

But clients WOULD like to view the data sometimes as though it were:

t x y z
----------------------------------------------------------------
t1 value when name='x' value when name='y' value when name='z'

if they do a SELECT on time=t1 and (name='x' or name='y' or name='z')

This seems like a fairly common desire. I know we could use Pivot Tables in
Excel, or otherwise do it on the client, but the highest-leverage solution
would be to present this abstraction in the server. Any ideas on how to do
this?