8 Acknowledgements

We thank Joachim Wambsganss and Bernard Schutz for inviting us to write the present review article. O.L. thanks members of the 2dFGRS team and the Leverhulme Quantitative Cosmology group for helpful discussions. Y.S. thanks all his students and collaborators for over many years, in particular Thomas Buchert, Takashi Hamana, Chiaki Hikage, Yipeng Jing, Issha Kayo, Hiromitsu Magira, Takahiko Matsubara, Hiroaki Nishioka, Jens Schmalzing, Atsushi Taruya, Kazuhiro Yamamoto, and Kohji Yoshikawa among others, for enjoyable and fruitful collaborations whose results form indeed the important elements in this review. Y.S. is also grateful for the hospitality at the Institute of Astronomy, University of Cambridge, where the most of present review was put together and written up for completion. O.L. acknowledges a PPARC Senior Research Fellowship. We also thank Idit Zehavi for permitting us to use Figure 28.

Numerical simulations were carried out at the ADAC (Astronomical Data Analysis Center) of the National Astronomical Observatory, Japan (project ID: mys02, yys08a). This research was also supported in part by the Grants-in-Aid from Monbu-Kagakusho and the Japan Society of Promotion of Science.