huge file in pg_xlog and base

["Nicola Benaglia" <nico(dot)benaz(at)gmail(dot)com>]

Hi,
I have 6 little dbs, but I see that my base directory needs 213MB and
log are 114MB.
Here my folder structure and size:

3571    ./base/1
3487    ./base/10792
4691    ./base/10793
3707    ./base/16384
16618   ./base/16386
0       ./base/64673/pgsql_tmp
143697  ./base/64673
0       ./base/86171/pgsql_tmp
6133    ./base/86171
5790    ./base/89667
6401    ./base/106022
7926    ./base/106521
11597   ./base/120343
213615  ./base
160     ./pg_subtrans
0       ./pg_twophase
8       ./pg_multixact/members
8       ./pg_multixact/offsets
16      ./pg_multixact
865     ./global
16      ./pg_clog
0       ./pg_xlog/archive_status
114800  ./pg_xlog
0       ./pg_tblspc
329484  .


Could you please suggest me how to reduce that space (if possible)?

Thank you,
Nico