Drupal: The User Object Variables List

stdClass Object (
  [uid] => 5
  [name] => %%username%%
  [pass] => %%md5_coded_pass_string_here%%
  [mail] => %%my@email.com%%
  [mode] => %%0%%
  [sort] => %%0%%
  [threshold] => %%0%%
  [theme] =>
  [signature] =>
  [signature_format] => %%1%%
  [created] => %%1288623095%%
  [access] => %%1288697282%%
  [login] => %%1288623155%%
  [status] => %%1%%
  [timezone] => %%10800%%
  [language] => en
  [picture] => %%sites/default/files/pictures/picture-5.jpg%%
  [init] => %%my@email.com%%
  [data] => %%serialized_data_here%%
  [ldap_authentified] => %%1%%
  [ldap_dn] =>%%uid=username,ou=Users,dc=example,dc=com
  [ldap_config] => %%1%%
  [ldap_drupal_roles] => %%Array ()%%
  [picture_delete] =>
  [picture_upload] =>
  [form_build_id] => %%form-5d79ba2fcb09b8ddb391cc3f648b88a4%%
  [roles] => %%Array ([2] => authenticated user)%%
  [domain_user] => %%Array ( [-1] => -1 )%%
  [referral_link] => %%referral/77777733%%
  [heartbeat_relations] => %%Array ( [5] => 5 )%%
)

In case you need the object returned by user_load($uid) drupal function, this is it. Of course, elements increase or decrease based on the modules enabled. For example elements [domain_user] and [ldap_dn] exist only because domain and ldap modules are used in my installation.